core
/
eccodes
mirror of https://github.com/ecmwf/eccodes.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

ECC-1114: Official request for Mercator grid support (geoiterator)

This commit is contained in:
Shahram Najm 2020-05-15 16:49:12 +01:00
parent 5383768bfd
commit f0c1c57fa1
1 changed files with 4 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
src/grib_iterator_class_mercator.c
View File

@ -102,7 +102,7 @@ static void init_class(grib_iterator_class* c)
/* Adjust longitude (in radians) to range -180 to 180 */
static double adjust_lon_radians(double lon)
{
if (lon > M_PI) lon -= 2 * M_PI;
if (lon > M_PI) lon -= 2 * M_PI;
if (lon < -M_PI) lon += 2 * M_PI;
return lon;
}
@ -111,7 +111,7 @@ static double adjust_lon_radians(double lon)
* From the book "Map Projections-A Working Manual-John P. Snyder (1987)"
* Equation (7–9) involves rapidly converging iteration: Calculate t from (15-11)
* Then, assuming an initial trial phi equal to (pi/2 - 2*arctan t) in the right side of equation (7–9),
* calculate phi on the left side. Substitute the calculated phi) into the right side,
* calculate phi on the left side. Substitute the calculated phi into the right side,
* calculate a new phi, etc., until phi does not change significantly from the preceding trial value of phi
*/
static double compute_phi(
@ -129,8 +129,8 @@ static double compute_phi(
con = eccent * sinpi;
dphi = M_PI_2 - 2 * atan(ts * (pow(((1.0 - con) / (1.0 + con)), eccnth))) - phi;
phi += dphi;
if (fabs(dphi) <= 0.0000000001)
return (phi);
if (fabs(dphi) <= EPSILON)
return phi;
}
*error = GRIB_INTERNAL_ERROR;
return 0;