Describe - Maple Programming Help

Home : Support : Online Help : System : Help : Describe

Describe

generates a brief description of a procedure, module, or other object

 Calling Sequence Describe( name )

Parameters

 name - the name of a procedure, module, or other Maple object

Description

 • The Describe command generates a brief description of a procedure, module, or other Maple object based on information stored within it.
 • For procedures, the description is generated from any description strings in the procedure, and its calling sequence.
 • Module descriptions are generated from description strings in the module, followed by an indented list generated by calling Describe recursively on each exported member of the module.
 • The description of other Maple objects consists of the type of the object, and its value (possibly abbreviated).

Examples

 > $\mathrm{Describe}\left(\mathrm{Digits}\right)$
 Digits::integer = 10
 > $\mathrm{Describe}\left(\mathrm{ImageTools}\right)$
 # an image processing package module ImageTools:     # clip intensity to specified levels     Clip( img::ImageTools:-Image,           { high::{realcons, identical(NULL)} := NULL, inplace::truefalse := false, low::{realcons, identical(NULL)} := NULL, output::{ImageTools:-Image, identical(NULL)} := NULL }, $) Create( height::{nonnegint, range(integer)} := 0, width::{nonnegint, range(integer)} := 0, layers::{1, 3, 4, identical(NULL), 1 .. {3, 4}} := NULL, data::{Array, Matrix, table, procedure, list(procedure), set(=), listlist(realcons), listlist(list(realcons))} := {}, { background::{realcons, list(realcons), identical(black,white)} := ':-black', channels::identical(NULL,1,3,4) := NULL, copy::truefalse := false, fit::truefalse := false, format::identical(Array,Matrix) := Array, order::identical(C_order,Fortran_order) := 'C_order' },$ ) :: ImageTools:-Image     module Draw:         Line( )         Circle( )         FilledCircle( )         Text( )         TextSize( )         FilledRectangle( img, x0, y0, x1, y1, color )     # embed images in an open worksheet     Embed( imgarg::{list({list(Image), Image}), Image},            { exterior::identical(group,all,none) := ':-all', interior::identical(group,all,none) := ':-all', mode::identical(direct,task) := ':-direct', tempdir::string := GetTempDir(), title::{string, identical(NoUserValue)} := ':-NoUserValue', titleposition::identical(top,bottom) := ':-bottom' }, $) # compute the entropy of the layers of an image Entropy( img, N::posint := 256, { autorange::truefalse := false, range:::-range(numeric) := 0 .. 1 },$ )     # flip an image horizontally or vertically     Flip( img::ImageTools:-Image, dir::identical(horizontal,vertical),           { inplace::truefalse := false, output::{ImageTools:-Image, identical(NULL)} := NULL }, $) Formats::set = {BMP, JPEG, TIFF} # adjust the gamma of an image; values < 1 lighten, values > 1 darken Gamma( img::ImageTools:-Image, gamma::realcons, { inplace::truefalse := false, output::{ImageTools:-Image, identical(NULL)} := NULL },$ )     # return height of image, in pixels     Height( img::ImageTools:-Image, info::identical(size,range,lower,upper) := ':-size', $) Image::symbol = ImageTools:-Image # return number of layers in image Layers( img::ImageTools:-Image, info::identical(size,lower,upper,range) := ':-size',$ )     # mask intensity of an image with another image     Mask( img::ImageTools:-Image, mask::ImageTools:-Image, $) # preview an image in the worksheet as a thumbnail plot module Preview( img::ImageTools:-Image, maxH::{posint, identical(NULL)} := NULL, maxW::{posint, identical(NULL)} := NULL, { chars::string := "@Oo*+=~- ", method::identical(bspline,nearest) := ':-bspline', output::identical(image,text) := ':-image' },$ )         # preview an image in the worksheet as a thumbnail plot         Preview( img::ImageTools:-Image, maxH::{posint, identical(NULL)} := NULL, maxW::{posint, identical(NULL)} := NULL,                  { chars::string := "@Oo*+=~- ", method::identical(bspline,nearest) := ':-bspline', output::identical(image,text) := ':-image' }, $) # compute the quality of a reconstructed image Quality( img_r::ImageTools:-GrayImage, img_s::ImageTools:-GrayImage, meas::identical(mse,psnr,rmse,snr) := ':-mse', { peak::realcons := 1 },$ )     # read an image from a file or URL     Read( input::string, img::{ImageTools:-Image, identical(NULL)} := NULL,           { format::identical(BMP,JPEG,TIFF) := NULL, output::{ImageTools:-Image, identical(NULL)} := NULL }, $) # rotate an image in increments of 90 degrees module Rotate( img::ImageTools:-Image, angle::{integer, identical(left,right)}, { output::{ImageTools:-Image, identical(NULL)} := NULL },$ )         # rotate an image in increments of 90 degrees         Rotate( img::ImageTools:-Image, angle::{integer, identical(left,right)},                 { output::{ImageTools:-Image, identical(NULL)} := NULL }, $) # scale the size of an image Scale( img::ImageTools:-Image, scaleY::{realcons, integer .. integer}, optScaleX::{realcons, identical(NULL), integer .. integer} := NULL, { antialias::{posint, identical(none)} := ':-none', method::identical(bspline,nearest) := ':-bspline' },$ )     # stack images horizontally or vertically     Stack( img_list::list(ImageTools:-Image), dir::identical(horizontal,vertical) := ':-horizontal',            { halign::identical(left,center,right) := ':-left', valign::identical(top,center,bottom) := ':-top' }, $) # convert an image to an RGB representation ToRGB( img::ImageTools:-Image, { output::{ImageTools:-ColorImage, identical(NULL)} := NULL },$ )     # convert an image to an RGBA representation     ToRGBA( img::ImageTools:-Image,             { output::{ImageTools:-ColorAImage, identical(NULL)} := NULL }, $) :: ImageTools:-ColorAImage # display images in a maplet View( { borderheight::posint := 120, borderwidth::posint := 80, maxmapletheight::posint := 800, maxmapletwidth::posint := 800, tempdir::string := GetTempDir(), title::string := "Image View" } ) # return width of image, in pixels Width( img::ImageTools:-Image, info::identical(size,range,lower,upper) := ':-size',$ )     # write an image to a file     Write( file::string, image::ImageTools:-Image,            { format::identical(BMP,JPEG,TIFF) := FormatFromName(file,true), quality::{numeric, identical(NULL)} := NULL }, $) # create a checkerboard image Checkerboard( n::posint := 20, height::posint := 8, width::posint := height, { background::realcons := 0., foreground::realcons := 1.0 } ) ColorAImage::symbol = ImageTools:-ColorAImage ColorImage::symbol = ImageTools:-ColorImage # linearly transform the colors of an image ColorTransform( img::{ImageTools:-ColorAImage, ImageTools:-ColorImage}, m::Matrix(And(realcons,Not(infinity))), { inplace::truefalse := false, output::{ImageTools:-ColorAImage, ImageTools:-ColorImage, identical(NULL)} := NULL },$ )     # combine monochromatic images to create a color image     CombineLayers( img1::ImageTools:-GrayImage, img2::ImageTools:-GrayImage, img3::ImageTools:-GrayImage, img4::{ImageTools:-GrayImage, identical(NULL)} := NULL,                    { output::{ImageTools:-ColorAImage, ImageTools:-ColorImage, identical(NULL)} := NULL }, $) # compute the complement of an image Complement( img::ImageTools:-Image, peak::realcons := 1, { inplace::truefalse := false, output::{ImageTools:-Image, identical(NULL)} := NULL },$ )     # apply a spatial convolution mask/kernel to an image     Convolution( image::ImageTools:-Image, kernel::rtable,                  { edges::{numeric, identical(compute,leave)} := ':-compute', exterior::{numeric, identical(ignore)} := ':-ignore', shape::identical(same,full,valid) := ':-same', weight::{numeric, identical(none)} := ':-none' }, $) # scale intensity to a given range FitIntensity( img::ImageTools:-Image, intensity::range(And(realcons,Not(infinity))) := 0 .. 1, channel::{1, 2, 3, 4, identical(all)} := 'all', { inplace::truefalse := false, output::{ImageTools:-Image, identical(NULL)} := NULL },$ )     # guess the image format from the filename     FormatFromName( file::string, errorOnFailure::truefalse := false, $) # extract one layer from a colored image GetLayer( img::{ImageTools:-ColorAImage, ImageTools:-ColorImage}, layer::{1, 2, 3, 4}, { output::{ImageTools:-GrayImage, identical(NULL)} := NULL },$ )     # extract a subimage from an image     GetSubImage( img::ImageTools:-Image, row::integer, col::integer, ht::posint, wd::posint,                  { output::{ImageTools:-Image, identical(NULL)} := NULL, reindex::truefalse := false }, $) GrayImage::symbol = ImageTools:-GrayImage # convert HSV color image to RGB module HSVtoRGB( img::{ImageTools:-ColorAImage, ImageTools:-ColorImage}, { inplace::truefalse := false, output::{ImageTools:-ColorAImage, ImageTools:-ColorImage, identical(NULL)} := NULL },$ )         # convert HSV color image to RGB         HSVtoRGB( img::{ImageTools:-ColorAImage, ImageTools:-ColorImage},                   { inplace::truefalse := false, output::{ImageTools:-ColorAImage, ImageTools:-ColorImage, identical(NULL)} := NULL }, $) # compute a histogram of an image Histogram( img::ImageTools:-Image, buckets::posint := 256, { autorange::truefalse := false, centers::truefalse := false, cumulative::truefalse := false, normalized::truefalse := false, range:::-range(numeric) := 0 .. 1 },$ )     # measure intensity of layers of an image     Intensity( img::ImageTools:-Image, meas::identical(minimum,maximum,range,mean,variance,rms,energy) := ':-range', $) # pad image, increasing its size PadImage( img::ImageTools:-Image, ht_rng::{range(integer), identical(NULL)} := NULL, wd_rng::{range(integer), identical(NULL)} := NULL, { border::nonnegint := 0, bottom::{nonnegint, identical(NULL)} := NULL, fill::{numeric, list(numeric), identical(reflect,replicate)} := 0, left::{nonnegint, identical(NULL)} := NULL, reindex::truefalse := false, right::{nonnegint, identical(NULL)} := NULL, top::{nonnegint, identical(NULL)} := NULL },$ )     # plot intensity histogram of an image     PlotHistogram( img::ImageTools:-Image, buckets::posint := 256,                    { autorange::truefalse := false, cumulative::truefalse := false, decomb::truefalse := false, normalized::truefalse := false, range:::-range(numeric) := 0 .. 1 } )     # convert an image to grayscale     RGBtoGray( img::ImageTools:-Image,                { output::{ImageTools:-GrayImage, identical(NULL)} := NULL }, $) :: ImageTools:-GrayImage # convert RGB to HSV module RGBtoHSV( img::{ImageTools:-ColorAImage, ImageTools:-ColorImage}, { inplace::truefalse := false, output::{ImageTools:-ColorAImage, ImageTools:-ColorImage, identical(NULL)} := NULL },$ )         # convert RGB to HSV         RGBtoHSV( img::{ImageTools:-ColorAImage, ImageTools:-ColorImage},                   { inplace::truefalse := false, output::{ImageTools:-ColorAImage, ImageTools:-ColorImage, identical(NULL)} := NULL }, $) # convert RGB to YUV RGBtoYUV( img::{ImageTools:-ColorAImage, ImageTools:-ColorImage}, { inplace::truefalse := false, output::{ImageTools:-ColorAImage, ImageTools:-ColorImage, identical(NULL)} := NULL },$ )     # scale the intensities of selected layers of an image     ScaleIntensity( img::ImageTools:-Image, scale::realcons, offset::realcons := 0,                     { inplace::truefalse := false, layers::{posint, list(posint), identical(all,color)} := 'all', output::{ImageTools:-Image, identical(NULL)} := NULL } )     # insert a layer into an image     SetLayer( img::ImageTools:-Image, img_layer::ImageTools:-GrayImage, layer::{1, 2, 3, 4},               { inplace::truefalse := false, output::{ImageTools:-ColorAImage, ImageTools:-ColorImage, identical(NULL)} := NULL }, $) # insert a subimage into a main image SetSubImage( img::ImageTools:-Image, sub::ImageTools:-Image, row::{integer, identical(NULL)} := NULL, col::{integer, identical(NULL)} := NULL, { inplace::truefalse := false, output::{ImageTools:-Image, identical(NULL)} := NULL },$ )     # perform threshold operation on a grayscale image     module Threshold( img, threshold::{numeric, identical(NULL)} := NULL,                       { buckets::posint := 100, high::numeric := 1.0, low::numeric := 0., method::identical(both,above,below) := 'both' }, $) # perform threshold operation on a grayscale image Threshold( img, threshold::{numeric, identical(NULL)} := NULL, { buckets::posint := 100, high::numeric := 1.0, low::numeric := 0., method::identical(both,above,below) := 'both' },$ )     # convert an image to grayscale     ToGrayscale( img::ImageTools:-Image,                  { output::{ImageTools:-GrayImage, identical(NULL)} := NULL }, $) :: ImageTools:-GrayImage # transpose an image Transpose( img::ImageTools:-Image, { output::{ImageTools:-Image, identical(NULL)} := NULL },$ )     # return the type of an image     WhatTypeImage( image )     # convert YUV to RGB     YUVtoRGB( img::{ImageTools:-ColorAImage, ImageTools:-ColorImage},               { inplace::truefalse := false, output::{ImageTools:-ColorAImage, ImageTools:-ColorImage, identical(NULL)} := NULL }, \$ )     module ColouringProcedures:         HueToRGB( img::Array(datatype = float[8]) )         FlameToRGB( data::Array(datatype = float[8]), gam::numeric, samplesize::posint := 2 )