Ncl where function ucar. Everything NCL does happens only after a statement is entered. In a continuously stratified fluid, it is the natural frequency of the vertical oscillation of fluid parcels. This example reads data from a netCDF file and creates a 12-frame animation of contours over a polar stereographic map projection. rip_cape_2d. Computes convective available potential energy (CAPE) and convective inhibition (CIN) (deprecated version). If the input values are outside the model domain, then the appropriate return values will be set to the default missing value for an integer (-999 for versions 5. This function returns a 2 x dimsizes(p) array, where index 0 of the leftmost dimension contains the CAPE values, and index 1 of the leftmost dimension contains the CIN values. If no meta data is desired: eofunc_n and eofunc_ts_n . Assume further that you want to make a copy of this variable, but you don't want to assign any values to it just yet: xnew = new ( dimsizes (x), typeof (x),x@_FillValue) Example 4. linint2 uses bilinear interpolation to interpolate from one rectilinear grid to another. created, changed and deleted via NCL functions and syntax (see sections 2. Input array of any dimensionality. Draws two text strings at the bottom of the workstation to indicate the time the plot was created and other information. You will need to load your new script to use the new function: Computes the average of a variable regardless of dimensionality. Example 2 at betainc illustrates how to get the one-tailed probability. See the eof_ n _640. It uses the ECMWF formulation as described in. WRFUserARW. Given wind components u and v , uv2sfvpf computes the stream function and the velocity potential and returns the results in the arrays sf and vp. functions. However, note that for the float and double types, the string 'nan' (any case) is read as a valid numerical value. Missing values are ignored. If you have WRF data, then we recommend that you use the wrf_user_intrp3d function instead (see example 2 below). Computes a zonal mean meridional stream function using a modified definition of the CESM Processor zonal mean meridional stream function. 3. This function differs from vinth2p in the method it uses to extrapolate to levels below psfc. Other attributes similar to "scale" and "offset" will be recognized: Note: this function is slightly different than the built-in set of conversion functions (like floattointeger and shorttobyte ), because it NCL Home > Documentation > Functions > WRF wrf_times_c. Writes a weight file using the offline ESMF weight generator. The Python scripts use PyNGL to create the graphics and a mix of xarray and PyNIO to read the data. In version 6. Young (2003): "Static stability measures the gravitational resistance of an atmosphere to vertical displacements. Currently, the equiv_sample_size function will operate on the rightmost dimension only. Variables imported via NCL’s addfile or addfiles functions (Section 3) will have all available metadata automatically attached to the variable. This function is based upon a response by Dave Allured (NOAA Affiliate) to an question asked on ncl-talk@ucar. This has been fixed in NCL V6. 6. Computes the gradient of an array that is on a gaussian grid using spherical harmonics. This function computes equivalent reflectivity factor (in dBZ) at each model grid point assuming spherical particles of constant density, with exponential size distributions. It is identical to that function but a shorter name. 2. Return value The Brunt-Vaisala frequency (1/s) is a measure of bouyancy. There are three ways to install NCL version 6. Natgrid culls duplicate points. ncl is a library of user-contributed functions written in NCL. 6 Statements The dim_stddev_n function computes the sample standard deviation of all elements of the dimensions indicated by dims for each index of the remaining dimensions. wrf_cape_2d. "V n " - change vertical spacing. Detailed document on NCL core language (syntax, variables, data types, array subscripting, command line options, etc. One or more values of any dimension. As the boxplot code does not use a gsn drawing function to construct the boxplot, note that the resources ESMF_regrid_1. copy_VarAtts. vertical_average__X = SUM[x*dp]/SUM[dp] ; iopt=0 vertical_integral_X = SUM[x*dp] ; iopt=1. It sorts the non-missing data values and uses the index values to extract the dectile, octile, sextile, quartile, tritile values. The supported file must have been opened as either read/write ("w") or create ("c"). A combination of the Mini-Language Manual with an excellent introduction to NCL graphics. x and NCL contributed. Prototype procedure PopLatLon ( x : numeric, grd_src : string, grd_dst : string, method : string, area_type : string, date : string ) return_val: numeric Then, derive and plot the velocity potential and stream function with overlays of the divergent and rotational wind components. Interpolates data from an unstructured (randomly-spaced) grid to a 3D grid using inverse distance weighted interpolation. Recommended for users who are just learning NCL, or users who want to create more high-end NCL graphics. The mixture of Pa for psfc and mb for plevo and p0 is specified by that source routine. NCL Home > Documentation > Functions > Empirical orthogonal functions eofunc_n. wind_4. This example also uses a resource file and shows how to create a function in an NCL script. Translates numeric time coordinates to calendar times ( temporary function; see the 6. Use eofunc_ts_n if your rightmost dimension is not time, to avoid having to reorder the input array. 5. This function is based on "dbzcalc. ncl - does the regridding in a single call to ESMF_regrid; ESMF_wgts_1. It results from fundamental buoyant adjustments, and so it is determined by the vertical stratification of density or potential temperature. Built-in NCL functions and procedures. This function converts any snumeric data or string to integer values. While the function allows mixed types, it is best to always use n and m of the same type. Use several Linux/Unix tools to create a UTC (Coordinated Universal Time) time. If you want to weight the input data values, calculate NCL Home > Documentation > Functions > General applied math atan2. The fourth argument allows the dimension to be defined as unlimited. Command line options and arguments. Computes maximum NCL Graphics: Boxplots. ncl gsun09n. Here are some sample function codes and their purposes: "F n " - change font in midstring. This example was taken from the "regrid_1. Convert omega vertical velocity (Pa/s) to (m/s). A scalar or one-dimensional array of indices. Carriage y = new (5,double,0) printVarSummary (y) Example 3. Plot a wind rose diagram where different colors are used to differentiate speed ranges. An array of one or more numeric values of any dimensionality. In this case, it will be set to the missing value, which is indicated by q Given a scalar array T on a global rectilinear grid, compute the latitudinal and longitudinal derivatives. The Linux/Unix command date -u returns the time as GMT (Greenwich Mean Time). Read and process a 4d array. NCL Home > Documentation > Functions > General applied math, Statistics avg. The returned information (t-values) can be used to create confidence bounds . No missing values are allowed in the input data arrays. A one-dimensional logical array. venn2_difference. "B" or "B n " - add subscripts. x. Using the provided weight file, regrids data from one lat/lon grid to another. 0 and earlier, the SLATEC version of this function had a bug that caused this function to potentially return the wrong coefficients in cases where you had multiple leftmost dimensions. Compute a simplified human discomfort index. Font definitions These function codes affect the selection of characters from the pwritx_database font: R selects the Roman font. This function is intended for large dataset sizes. Supported data format information. Function-Type Listing; Resources. If missing values are present, then linint2 will perform the bilinear interpolation at all points possible ESMF. See comments in the routine for more details. The modified definition used is given by: / PS | 2 pi a cos (lat) | ZONAL_MPSI (lev,lat) = --------------- | V (lev,lat) dp g | | / p. copy_VarCoords. This function computes a weighted area average. 4. gradLatLon = grad_latlon_cfd (T, T&lat T&lon, True, False) T_grad_lat = gradLatLon [0] ; for clarity; explicitly extract variables from returned 'list'. ) dsgrid3. Evaluates the inverse chi-squared distribution function. cla_sq. For historical reasons, NCL contains a suite of EOF functions . Computes empirical orthogonal functions (EOFs, aka: Principal Component Analysis), given an index that specifies which dimension contains the number of observations. Converts WRF variable "Times" which is of type character to user specified numeric units. Use lspoly_n if you want to specify which dimension(s) to do the calculation across. Overlays contour and vector plots on a WRF-ARW map background. Creates an array of equally-spaced integer, long, or int64 values. ) Reference Cards. Note: for NCL versions 6. Computes the average of a variable regardless of dimensionality. Must be same size as x, minus the rightmost dimension. Example 9 - animated contours over a map. Returns a reference to the current Workspace object. NOTE: NCL's dimension reordering Dimension reordering may have to be used to make 'time' the rightmost dimension. There are 17 different kinds of statements: assignment, procedure call, function definition, procedure definition, block, do NCL function codes allow you to add special formatting to any resource that creates a graphical title or label of any sort. 0 release notes for details). This function places values from a smaller 1D array onto a larger 1D array, given the indexes into the larger 1D array, and then reshapes it to a multi-dimensional The filedimdef procedure is used to pre-define dimensions in a file. Returns the unique element symmetric differences between two arrays. The input grid may be cyclic in the x direction. Calculates gridded binned averages and counts on a rectilinear grid using randomly spaced data. Currently, netCDF files only allow one dimension to be unlimited, and this dimension must be the leftmost dimension of your dsgrid2s. wgtx. Available in version 4. The function gc_latlon returns the great circle distance between two points on the surface of the globe in units specified by the value of iu. Statements are the fundamental element of NCL. The arguments are variables from WRF data. optETS. Assume T is a 4D array with dimensions ntim x klev x nlat x mlon and dp is an array of length klev. Statements are not restricted to being a single line of source, and statements can be nested within statements. If var_to already contains an attribute of the same name as one of var_from 's attributes, then it is deleted and the new one copied over. Given two variables X and Y, the bivariate joint probability distribution returned by the pdfxy function indicates the probability of occurrence defined in terms of both X and Y. NCL Home > Documentation > Functions > NCL object routines NhlGetWorkspaceObjectId. Calculates "nice" values for endpoints and spacing to be used for creating a series of equally-spaced levels through the data domain. ncl to use the boxplot function. Creates a contour plot from ARW WRF model output. Determines if a given year is a leap year. Dear all Is there any functions to convert the negetive data of a dimension NCL Home > Documentation > Functions > General applied math ceil. If the regression information for a single best fit line for 1-dimensional x and y data is desired, then regline is the appropriate choice. Returns a grid that contains a land/sea mask given any latitude and longitude array. A scalar integer equal to the number of latitude points PER hemisphere. However, other users found the functionality useful and they are now distributed with NCL. 0 and later. This means that it divides by one less than the total number of non-missing values (1 Jul 17, 2013 · In reply to: Mahesh Varma: ""month_to_annual" function" Contemporary messages sorted : [ By Date ] [ By Thread ] [ By Subject ] [ By Author ] [ By messages with attachments ] This archive was generated by hypermail 2. If missing values are present, then linint1 will perform the piecewise linear interpolation at all points possible, but will return missing values at coordinates which could not be used. Return value. WRF. Further, the function assumes the time steps are equally spaced. Note: You must load shea_util. As of version 6. Compute the human discomfort index due to excessive heat and humidity using the Stull wet bulb temperature ( wetbulb_stull ). ncl functions. Technically, this function calculates the sample standard deviation. This function is an alias for the function tointeger. 13). Description The NCAR Command Language (NCL), a product of the Computational & Information Systems Laboratory at the National Center for Atmospheric Research (NCAR) and sponsored by the National Science Foundation, is a free interpreted language designed specifically for scientific data processing and visualization. The results are the same as those of the GNU "gfortran" compiler. edu. To test the EOF time series for orthogonality, compute correlations. The interpolation is first performed in the x direction, and then in the y direction. A multi-dimensional integer array or scalar value representing years. opt. Generally, this is not true. 0 Return value. copy_VarCoords_1. Computes the gradient of an array that is on a fixed grid using spherical harmonics. NCL contributed. This function does not draw the boxplot or advance the frame, so you must do this yourself by calling draw and frame after the boxplot is created. Regrids data from one lat/lon grid to another, using ESMF software. NCL keyword listing. If any missing values are encountered in a particular 2D input grid, then all of natgrid accepts a set of randomly-positioned 2D point coordinates, together with function values at those coordinates, and returns a set of interpolated function values at coordinates on a user-specified rectangular grid. Then use NCL's Coordinate Subscripting to subset the returned 1D array. The returned variable contains two components: [0] =meridional; [1] zonal. Create a time series of area averages; band-pass filter the resulting area-averaged time series and calculate other statistics. ncl : A black and white version of example 3. Description NCL Home > Documentation > Functions > Regridding, CESM, Oceanography PopLatLon. The functions and procedures can also be viewed by category (i. Windows users will need to use the Linux subsystem in order to install and run NCL. Computes convective available potential energy (CAPE), convective inhibition (CIN), lifted condensation level (LCL), and level of free convection (LFC) (deprecated version). NCL language reference. The linint1 function uses piecewise linear interpolation to interpolate from one series to another. Transfers the _FillValue attribute from one variable to another. Description. Complete Listing; am (annotation manager) Subscribe to ncl-install and then email your question to ncl-install@ucar. ncl: (a) Read files containing year-month data, (b) create climatologies spanning user specified years (c) plot November-April and May-October climatologies over a user specified region. Note: for WRF variable names and their definitions, you can easily check them by using "ncl_filedump": ncl_filedump wrfout_d01_2000-01-24_12:00:00. Prototype function wgt_areaave2 ( q : numeric, wgt [*][*] : numeric, opt : integer ) return_val: float or double Arguments q shea_util. Coerces values of type character to values of type string ( deprecated; use tostring ). Returns an array dimensioned the same as value. Prototype function gaus ( nlat [1] : integer or long ) return_val [2*nlat,2] : double Arguments nlat. Note: in most of the WRF data analysis functions (unless otherwise specified), if any of the input arrays contain missing data, then the Description. For plotting, the returned values which have units (1/s) are often multiplied by 86400 (s/day) to get units of (1/day). Draws an outline around missing data in vector and streamline plots. Section 2. This function returns a reference to the workspace NCL Home > Documentation > Functions > Date routines isleapyear. The series may be cyclic in the X direction. Make the yrStrt and yrLast span the required years. Use wrf_user_ll_to_xy instead. Return value Performs tapering (filtering) of the spherical harmonic coefficients. NCL and Python Transition Guide Examples. Prototype Description. There is also a link where you can get one and two-tailed probabilities via the WWW. extval_pareto. This function converts short data to float using the "scale" and "offset" attributes (if present), and preserves metadata. Generate a plot using the output from band_pass_area_time . Compute an environmental stress index (ESI) which is an alternative to the wet bulb globe temperature (WBGT). THIS IS THE PREFERRED METHOD for installing NCL on MacOSX and Linux systems. Command line editing in interactive mode. Sets map plotting resources based on an input WRF-ARW file. Returns the indices where the input is True. Available in version 6. The NCL functions specx_anal and specxy_anal perform the temporal-to-frequency transformation via the Fast Fourier Transform (FFT). ncl for convenience. This returns a string of the form: Wed Jan 12 19:40:25 MST 2005. ncl" function, etc). Plots a basic wind rose. This function locates the closest y/x point to the input latitude/longitude. Calculates the probability (PDF) and cumulative (CDF) distribution functions of the Pareto distributions (Generalized, Type I, TYpe II) given the shape, scale and location parameters. 0) or singly dimensioned array of size "lon" (x) containing the weights. Returns a list of strings that contain the given substring (case sensitive). This function will return a long if on a 64-bit system and the index value is >= 2 GB. Installing NCL from a precompiled binary. Any input value that is out of range for an integer will be returned as a missing value. Hence, the source time series must be pre-treated (aka, "pre-whitening"). ncl. This procedure does not handle missing values (defined by the _FillValue attribute). It does not do anything special with replicated values. NCL has robust file input and output. nc Example 1. Example 3. Return value climo_6. Documentation under construction. Date routines. Where can I see a list of all the NCL functions and procedures? See the alphabetical list of NCL functions and procedures. The main purpose of this page is to help ease the transition from NCL to Python by providing both NCL and Python versions of scripts that read/write ASCII and NetCDF files and/or produce graphics. ncl script, which is a library of functions and procedures written to help users plot ARW WRF model data. NOTE: This function is documented as weighted vertical sum/average but it can be used for any weighted quantity along any coordinate. Calculates the atmosphere's relative angular momentum. Prototype function isleapyear ( year : integer ) return_val [dimsizes(year)] : logical Arguments year. NCL Home > Documentation > Functions > General applied math wgt_areaave2. Prototype function sqrt ( value : float or double ) return_val [dimsizes(value)] : float or double Arguments value. NCL Home > Documentation > Functions > General applied math sqrt. Interpolates float data from an unstructured (randomly-spaced) grid to a rectilinear grid using inverse distance weighted interpolation. TIME = yyyymm_time (1901, 2001, "integer") time = TIME ( { 190104:200109 }) ; coordinate subscripting print (time) The above returns a 1D array The asciiread function is used to read ASCII data. The default at the beginning of a string is to use the Roman font. To run this example, you must download the following files: gsun09n. G selects the Greek font. "graphics routines", "interpolation"), and by type (that is, whether it's a built-in function, a "contributed. If opt = 1, then if any point in q is missing, the area average is not computed. Prototype function atan2 ( y : numeric, x : numeric ) return_val [dimsizes(y)] : float or double Arguments y. Translates numeric time coordinates to calendar times. Copies all of a variable's attributes from one variable to another. Calculates the corresponding temperature, density, and height based on the 1976 U. Apr 7, 2011 · From: Guangtao dong <donggt2010_at_nyahnyahspammersnyahnyah> Date: Thu Apr 07 2011 - 01:41:48 MDT. Prototype function NhlGetWorkspaceObjectId ( ) return_val [1] : graphic Description. regCoef is designed to work with multi-dimensional x and y arrays. f" in RIP. The mod function is more general. Returns the smallest integral value greater than or equal to each input value. . Retrieves the radius of a sphere used in spherical harmonic routines. 1. Calculate the weighted vertical average and/or sum along a specific dimension. Originally, these functions were written by Dennis Shea for personal use. These optional arguments alter the default behavior of the function. venn2_intersection. Writes the description of a lat/lon grid to a SCRIP file. regCoef computes the linear regression coefficient via least-squares. Assume x is some multi-dimensional variable of unknown type and a missing value. 0. 0, this can be of type integer or long. This function is identical to uv2vrF, except the return value will have metadata added based on metadata attached to u and v. An array of one or more values ≥ 0. Over time, others have written functions that have been included in shea_util. ncl functions (meteorology) NCL Home > Documentation > Functions > Meteorology omega_to_w. e. Example 2. If neval=3 then. Return value Echo the current date and time to the screen: begin system ("date") end. wind_rose. This function interpolates terrain following data to either a given pressure or height level. If opt = 0, the area average is calculated using available non-missing data. NCL has a modulus algebraic operator, % , which requires that the arguments be integers. See Also NCL Home > Documentation > Language If Statements if (scalar_logical_expression) then statement list end if if (scalar_logical_expression) then statement list else Remove all but the modified "wrf_user_getvar" function from your copy, rename the function ("wrf_user_getvar2"), and rename the file ("my_new_script. For all the integer types, the prefix Description. standard atmosphere, given the pressure. S. ncl : Example of divergence calculated via spherical harmonics ( uv2dvG ) and centered finite differences uv2dv_cfd . This greatly simplifies coding and access to each variable’s metadata. This is the long-standing method where you download a precompiled version of NCL Home > Documentation > Functions > Array query ind. EOF: Standard Empirical Orthogonal This procedure copies all of a variable's attributes from var_from to var_to. The following three one-dimensional functions all do the same thing, differing only in the type of the input and output arrays: csa1 (generic input/output); csa1s (single input/output); csa1d (double input/output). NCL data types overview. The function code 'F', without a following integer, implies a return to the font specified by the txFont resource. The interface is identical. Typically, this will the time dimension. "S" or "S n " - add superscripts. Reference Manual. Computes the square root of its input. ncl scripts below for examples of using the new xxxx _n functions. ncl" example on the original regridding examples page, which uses the linint2 function to do the regridding. Create a yyyymm variable named "time" that spans April 1901 to September 2001. Missing data are allowed. Example 1. RIP. Values must be >= 0. heat_stress. A multi-dimensional numerical array of surface pressures. A scalar numeric value equal to the lower limits of integration. where V is the zonal mean meridional wind (calculated ESMF_regridding. In most applications, this means the data must be NCL Home > Documentation > Functions > Meteorology stdatmus_p2tdz. Creates a basic pie chart. If q has no missing values, wgt_areaave is equivalent to: q _ave = SUM[ q * wgty * wgtx ]/SUM[ wgty * wgtx] Use the wgt_areaave_Wrap function if metadata retention is desired. Use an NCL script to pass environment variables to another NCL script that uses getenv to access the settings. Creates a map background for ARW WRF model data. Overlays WRF plot (s) on a WRF-ARW map background ( deprecated ). It does not perform linear interpolation like "Minitab". Demonstrates hybrid data analysis, which uses built-in functions as well as functions in contributed. nice_mnmxintvl. This function was deprecated in NCL version 5. 2: Using conda. The recommended functions are: eofunc_n_Wrap, eofunc_ts_n_Wrap and eofunc_north . A scalar (typically 1. The Workspace object manages blocks of memory used by the NCL objects. 0 , this function was upgraded to return a "_FillValue" attribute. res. Available in version 5. One or more numeric values of any dimension. Copies all named dimensions and coordinate See the full list of WRF functions. NCL Home > Documentation > Functions > Lat/Lon functions gaus. Creates a box percentile plot. Copies all named dimensions and coordinate variables from one variable to another. Writes the description of a curvilinear grid to a SCRIP file. A multi-dimensional array containing the EOFs calculated using eofunc_n or eofunc_n_Wrap . Compute apparent temperature. Computes albedo via CESM model radiation variables. wind_5. Regrids a scalar variable on a POP grid to a lat/lon grid or vice-versa. 8 : Fri Jul 19 2013 - 15:39:06 MDT NCL: Probability Distribution Functions. assignFillValue. Use the eofunc_ts_Wrap function if metadata retention is desired. Computes the inverse tangent of (y/x) for numeric types. The probability distribution (frequency of occurrence) of an individual variable, X, may be obtained via the pdfx function. This is similar to the routine used within the CESM Processor. rip_cape_3d. It ignores missing values ( q @_FillValue). Examples. ( Deprecated version . Converts a mixed Julian/Gregorian date to a UT-referenced date. Prototype function str_match ( string_array : string, sub_string [1] : string ) return_val [*] : string Arguments string_array NCL Graphics: EOFs. ncl"). Calculates binned sums and counts over multiple invocations of the procedure on a rectilinear grid. Prototype function avg ( x : numeric ) return_val [1] : float or double Arguments x. Retrieve the current time and date and return as a string: TimeDate = systemfunc ("date") This returns a string of the form: TimeDate = "Tue Apr 11 14:30:44 MDT 2000". Evaluates the incomplete beta function. Computes Gaussian latitudes and weights. Some of the functions below are built into NCL, while some of them are part of the WRFUserARW. Remember that in NCL, indexing starts at 0, not 1. If datatype is a numeric type, then non-numeric characters are ignored and the numbers are read in the order they appear in the input file. Default script and shared library loading. The following attributes are also returned: gclat - the latitudes of points on the great circle (dimensioned nlat2 * npts, and includes the two input latitude points) gclon - the longitudes Metadata routines. If v3d has attributes "description" or "units", they will be returned with the output variable. The FFT implicitly assume the time series are 'cyclic'. See the uv2vrF page for full documentation and examples. A scalar numeric value equal to the upper limits of integration. 11-2. A logical variable to which various optional arguments may be assigned as attributes . If the input is float or double, then the fractional part is truncated. ncl - uses an existing weights file and does the regridding with a call to ESMF_regrid_with_weights. uv2sfvpf operates on a fixed grid. One or more values with the same dimension as y. ncl functions (spherical harmonic routines) The general documentation for Csagrid contains several complete examples. Create a string that uses single quotes (sq) to enclose command line assignment (CLA) statements for later use by NCL's system procedure. Prototype function ceil ( values : numeric ) return_val [dimsizes(values)] : float or double Arguments values. Writes the description of a lat/lon grid to The ttest uses the incomplete beta function ( betainc) to calculate the probability. Calculates the area average of a quantity using two-dimensional weights. chiinv. Must be set to True prior to setting the attributes which are assigned using the @ operator Estimates the shape, scale and location parameters for the Generalized Extreme-Value (GEV) distribution using Maximum-Likelihood Estimation (MLE). NCL Home > Documentation > Functions > String manipulation str_match. NCL data analysis example page. tConform = conform_dims ( dimsizes (x),t,0) will yield an array tConform that is dimensioned ntim x nlat x mlon where the contents of t are propagated to all dimensions of x. This function returns an array of the same type as x whose leftmost dimensions are the same as all but the last dimension of x, and whose rightmost dimensions are dims. Creating Graphical Output. Prototype function ind ( larray [*] : logical ) return_val [*] : integer or long Arguments larray. Plot a black and white wind rose diagram where different line thicknesses are used to differentiate speed ranges. ohloetucxvdwefyvbdxx