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diff --git a/docs/source/apps/proj.rst b/docs/source/apps/proj.rst new file mode 100644 index 00000000..a06df383 --- /dev/null +++ b/docs/source/apps/proj.rst @@ -0,0 +1,164 @@ +:. _proj: + +================================================================================ +proj +================================================================================ + + +.. Index:: proj + +Proj and invproj perform respective forward and inverse transformation of cartographic data to +or from cartesian data with a wide range of selectable projection functions. + + +Synopsis +******** +:: + + proj [ -bcCeEfiIlmorsStTvVwW [ args ] ] [ +args ] file[s] + invproj [ -bcCeEfiIlmorsStTwW [ args ] ] [ +args ] file[s] + + +Description +*********** +The following control parameters can appear in any order + +:: + + -b Special option for binary coordinate data input and output through standard input + and standard output. Data is assumed to be in system type double floating point + words. This option is to be used when proj is a son process and allows bypassing + formatting operations. + + -i Selects binary input only (see -b option). + + -C Check. Invoke all built in self tests and report. Get more verbose report by + preceding with the -V option). + + -I alternate method to specify inverse projection. Redundant when used with invproj. + + -o Selects binary output only (see -b option). + + -ta A specifies a character employed as the first character to denote a control line + to be passed through without processing. This option applicable to ascii input + only. (# is the default value). + + -e string + String is an arbitrary string to be output if an error is detected during data + transformations. The default value is: *\t*. Note that if the -b, -i or -o + options are employed, an error is returned as HUGE_VAL value for both return values. + + -E causes the input coordinates to be copied to the output line prior to printing the + converted values. + + + -l[p|P|=|e|u|d]id + List projection identifiers with -l, -lp or -lP (expanded) that can be selected + with +proj. -l=id gives expanded description of projection id. List + ellipsoid identifiers with -le, that can be selected with +ellps, -lu list of + cartesian to meter conversion factors that can be selected with +units or -ld + list of datums that can be selected with +datum. + + -r This options reverses the order of the expected input from longitude-latitude or + x-y to latitude-longitude or y-x. + + -s This options reverses the order of the output from x-y or longitude-latitude to + y-x or latitude-longitude. + + -S Causes estimation of meridinal and parallel scale factors, area scale factor and + angular distortion, and maximum and minimum scale factors to be listed between <> + for each input point. For conformal projections meridinal and parallel scales + factors will be equal and angular distortion zero. Equal area projections will + have an area factor of 1. + + -m mult + The cartesian data may be scaled by the mult parameter. When processing data in + a forward projection mode the cartesian output values are multiplied by mult + otherwise the input cartesian values are divided by mult before inverse projection. + If the first two characters of mult are 1/ or 1: then the reciprocal value of mult + is employed. + + -f format + Format is a printf format string to control the form of the output values. For + inverse projections, the output will be in degrees when this option is employed. + The default format is "%.2f" for forward projection and DMS for inverse. + + -[w|W]n + N is the number of significant fractional digits to employ for seconds output (when + the option is not specified, -w3 is assumed). When -W is employed the fields + will be constant width and with leading zeroes. + + -v causes a listing of cartographic control parameters tested for and used by the + program to be printed prior to input data. Should not be used with the -T + option. + + -V This option causes an expanded annotated listing of the characteristics of the + projected point. -v is implied with this option. + + -T ulow,uhi,vlow,vhi,res[,umax,vmax] + This option creates a set of bivariate Chebyshev polynomial coefficients that + approximate the selected cartographic projection on stdout. The values low and + hi denote the range of the input where the u or v prefixes apply to respective + longitude-x or latitude-y depending upon whether a forward or inverse projection + is selected. Res is an integer number specifying the power of 10 precision of + the approximation. For example, a res of -3 specifies an approximation with an + accuracy better than .001. Umax, and vmax specify maximum degree of the polynomials + (default: 15). + + +The ``+args`` run-line arguments are associated with cartographic parameters. Usage varies with +projection and for a complete description consult the `projection pages <../projections/index.html>`_ + +Additional projection control parameters may be +contained in two auxiliary control files: the +first is optionally referenced with the +``+init=file:id`` and the second is always processed +after the name of the projection has been established +from either the run-line or the contents +of +init file. The environment parameter +``PROJ_LIB`` establishes the default directory for a +file reference without an absolute path. This +is also used for supporting files like datum +shift files. + +One or more files (processed in left to right +order) specify the source of data to be trans- +formed. A - will specify the location of pro- +cessing standard input. If no files are speci- +fied, the input is assumed to be from stdin. +For ASCII input data the two data values must be +in the first two white space separated fields +and when both input and output are ASCII all +trailing portions of the input line are appended +to the output line. + +Input geographic data (longitude and latitude) +must be in DMS format and input cartesian data +must be in units consistent with the ellipsoid +major axis or sphere radius units. Output geo- +graphic coordinates will be in DMS (if the -w +switch is not employed) and precise to 0.001" +with trailing, zero-valued minute-second fields +deleted. + +Example +******* +The following script + +:: + + proj +proj=utm +lon_0=112w +ellps=clrk66 + -r <<EOF + 45d15'33.1" 111.5W + 45d15.551666667N -111d30 + +45.25919444444 111d30'000w + EOF + +will perform UTM forward projection with a stan- +dard UTM central meridian nearest longitude +112W. The geographic values of this example are +equivalent and meant as examples of various +forms of DMS input. The x-y output data will +appear as three lines of:: + + 460769.27 5011648.45 |