pygmt.grdinfo

pygmt.grdinfo(grid, *, per_column=None, tiles=None, geographic=None, spacing=None, force_scan=None, minmax_pos=None, region=None, nearest_multiple=None, verbose=None, coltypes=None, **kwargs)[source]

Get information about a grid.

Can read the grid from a file or given as an xarray.DataArray grid.

Full option list at https://docs.generic-mapping-tools.org/6.5/grdinfo.html

Aliases:

  • C = per_column

  • D = tiles

  • F = geographic

  • I = spacing

  • L = force_scan

  • M = minmax_pos

  • R = region

  • T = nearest_multiple

  • V = verbose

  • f = coltypes

Parameters:

  • grid (str or xarray.DataArray) –

    Name of the input grid file or the grid loaded as a xarray.DataArray object.

    For reading a specific grid file format or applying basic data operations, see https://docs.generic-mapping-tools.org/6.5/gmt.html#grd-inout-full for the available modifiers.

  • region (str or list) – xmin/xmax/ymin/ymax[+r][+uunit]. Specify the region of interest.

  • per_column (str or bool) – n|t. Format the report using tab-separated fields on a single line. The output is name w e s n z0 z1 dx dy nx ny [ x0 y0 x1 y1 ] [ med scale ] [ mean std rms ] [ n_nan ] registration gtype. The data in brackets are outputted depending on the force_scan and minmax_pos parameters. Use t to place file name at the end of the output record or, n or True to only output numerical columns. The registration is either 0 (gridline) or 1 (pixel), while gtype is either 0 (Cartesian) or 1 (geographic). The default value is False. This cannot be called if geographic is also set.

  • tiles (str or list) – xoff[/yoff][+i]. Divide a single grid’s domain (or the region domain, if no grid given) into tiles of size dx times dy (set via spacing). You can specify overlap between tiles by appending xoff[/yoff]. If the single grid is given you may use the modifier +i to ignore tiles that have no data within each tile subregion. Default output is text region strings. Use per_column to instead report four columns with xmin xmax ymin ymax per tile, or use per_column="t" to also have the region string appended as trailing text.

  • geographic (bool) – Report grid domain and x/y-increments in world mapping format. The default value is False. This cannot be called if per_column is also set.

  • spacing (str or list) – dx[/dy]|b|i|r. Report the min/max of the region to the nearest multiple of dx and dy, and output this in the form w/e/s/n (unless per_column is set). To report the actual grid region, append r. For a grid produced by the img supplement (a Cartesian Mercator grid), the exact geographic region is given with i (if not found then we return the actual grid region instead). If no argument is given then we report the grid increment in the form xinc[/yinc]. If b is given we write each grid’s bounding box polygon instead. Finally, if tiles is in effect then dx and dy are the dimensions of the desired tiles.

  • force_scan (int or str) –

    0|1|2|p|a.

    • 0: Report range of z after actually scanning the data, not just reporting what the header says.

    • 1: Report median and L1 scale of z (L1 scale = 1.4826 * Median Absolute Deviation (MAD)).

    • 2: Report mean, standard deviation, and root-mean-square (rms) of z.

    • p: Report mode (LMS) and LMS scale of z.

    • a: Include all of the above.

  • minmax_pos (bool) – Include the x/y values at the location of the minimum and maximum z-values.

  • nearest_multiple (str) – [dz][+a[alpha]][+s]. Determine minimum and maximum z-values. If dz is provided then we first round these values off to multiples of dz. To exclude the two tails of the distribution when determining the minimum and maximum you can add +a to set the alpha value (in percent): We then sort the grid, exclude the data in the 0.5*alpha and 100 - 0.5*alpha tails, and revise the minimum and maximum. To force a symmetrical range about zero, using minus/plus the maximum absolute value of the two extremes, append +s. We report the result via the text string zmin/zmax or zmin/zmax/dz (if dz was given) as expected by pygmt.makecpt.

  • verbose (bool or str) –

    Select verbosity level [Default is w], which modulates the messages written to stderr. Choose among 7 levels of verbosity:

    • q - Quiet, not even fatal error messages are produced

    • e - Error messages only

    • w - Warnings [Default]

    • t - Timings (report runtimes for time-intensive algorithms)

    • i - Informational messages (same as verbose=True)

    • c - Compatibility warnings

    • d - Debugging messages

  • coltypes (str) – [i|o]colinfo. Specify data types of input and/or output columns (time or geographical data). Full documentation is at https://docs.generic-mapping-tools.org/6.5/gmt.html#f-full.

Returns:

info (str) – A string with information about the grid.