proj(1) PROJ proj(1)
NAME
proj - Cartographic projection filter
SYNOPSIS
proj [-beEfiIlmorsStTvVwW] [args]] ([+opt[=arg] ...] | {crs}) file
...
invproj [-beEfiIlmorsStTvVwW] [args]] ([+opt[=arg] ...] | {crs})
file ...
DESCRIPTION
proj and invproj perform respective forward and inverse conversion of
cartographic data to or from cartesian data with a wide range of
selectable projection functions.
invproj may not be available on all platforms; in this case use proj -I
instead.
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 child process and allows bypassing
formatting operations.
-d <n>
New in version 5.2.0: Specify the number of decimals to round to in the
output.
-i Selects binary input only (see -b).
-I Alternate method to specify inverse projection. Redundant when
used with invproj.
-o Selects binary output only (see -b).
-t<a> Where 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>
Where string is an arbitrary string to be output if an error is
detected during data transformations. The default value is a
three character string: *\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<[=id]>
List projection identifiers that can be selected with +proj.
proj -l=id gives expanded description of projection id, e.g.
proj -l=merc.
-lp List of all projection id that can be used with the +proj
parameter. Equivalent to proj -l.
-lP Expanded description of all projections that can be used with
the +proj parameter.
-le List of all ellipsoids that can be selected with the +ellps
parameters.
-lu List of all distance units that can be selected with the +units
parameter.
-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 meridional 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 meridional 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>
Where 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<n> Where n is the number of significant fractional digits to employ
for seconds output (when the option is not specified, -w3 is
assumed).
-W<n> Where n is the number of significant fractional digits to employ
for seconds output. When -W is employed the fields will be
constant width 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.
-V This option causes an expanded annotated listing of the
characteristics of the projected point. -v is implied with this
option.
The +opt run-line arguments are associated with cartographic
parameters. 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_DATA establishes
the default directory for a file reference without an absolute path.
This is also used for supporting files like datum shift files.
New in version 9.3.0: {crs} is one of the possibilities accepted by
:c:proj_create(), provided it expresses a projected CRS, like a WKT
string, an object code (like "EPSG:32632") a PROJJSON string, etc. The
projection computed will be those of the map projection implied by the
transformation from the base geographic CRS of the projected CRS to the
projected CRS.
One or more files (processed in left to right order) specify the source
of data to be converted. A - will specify the location of processing
standard input. If no files are specified, 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 or
decimal degrees format and input cartesian data must be in units
consistent with the ellipsoid major axis or sphere radius units. Output
geographic 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 +zone=12 -r <<EOF
45d15'33.1" 111.5W
45d15.551666667N -111d30
+45.25919444444 111d30'000w
EOF
will perform UTM zone 12 forward projection. The default +ellps=GRS80
is used as no +ellps was specified. 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:
460770.43 5011865.86
This other example
proj EPSG:6421 -V <<EOF
-120 35.8
EOF
Will perform the projection of the coordinates in "NAD83(2011) /
California zone 4" (EPSG:6421) into its geographic system,
"NAD83(2011)", showing the expanded annotated listing. The output will
appear as:
#Lambert Conformal Conic
# Conic, Sph&Ell
# lat_1= and lat_2= or lat_0, k_0=
# +proj=lcc +lat_0=35.3333333333333 +lon_0=-119 +lat_1=37.25 +lat_2=36
# +x_0=2000000 +y_0=500000 +ellps=GRS80
#Final Earth figure: ellipsoid
# Major axis (a): 6378137.000
# 1/flattening: 298.257222
# squared eccentricity: 0.006694380023
Longitude: 120dW [ -120 ]
Latitude: 35d48'N [ 35.8 ]
Easting (x): 1909606.87
Northing (y): 552253.58
Meridian scale (h) : 1.00004382 ( 0.004382 % error )
Parallel scale (k) : 1.00004382 ( 0.004382 % error )
Areal scale (s): 1.00008765 ( 0.008765 % error )
Angular distortion (w): 0.000
Meridian/Parallel angle: 90.00000
Convergence : -0d35'47.714" [ -0.59658715 ]
Max-min (Tissot axis a-b) scale error: 1.00004 1.00004
OTHER PROGRAMS
The proj program is limited to converting between geographic and
projected coordinates within one datum.
The cs2cs program operates similarly, but allows translation between
any pair of definable coordinate reference systems, including support
for datum translation.
SEE ALSO
cs2cs(1), cct(1), geod(1), gie(1), projinfo(1), projsync(1)
BUGS
A list of known bugs can be found at
https://github.com/OSGeo/PROJ/issues where new bug reports can be
submitted to.
HOME PAGE
https://proj.org/
AUTHOR
Gerald I. Evenden
COPYRIGHT
1983-2023, PROJ contributors
9.3 01 Dec 2023 proj(1)
proj 9.3.1 - Generated Wed Dec 20 10:04:34 CST 2023