# Error in IOAPI-3.2 coordinate transform routines

**URL:** <https://forum.cmascenter.org/t/error-in-ioapi-3-2-coordinate-transform-routines/2665>\
**Category:** I/O API\
**Created:** [September 24, 2021, 11:52am UTC](https://forum.cmascenter.org/t/error-in-ioapi-3-2-coordinate-transform-routines/2665 "2021-09-24T11:52:22Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![phy](https://avatars.discourse-cdn.com/v4/letter/p/35a633/32.png) [@phy](https://forum.cmascenter.org/u/phy)\
**Post date:** [September 24, 2021, 11:52am UTC](https://forum.cmascenter.org/t/error-in-ioapi-3-2-coordinate-transform-routines/2665/1 "2021-09-24T11:52:22Z")

</div>

Hi,

I’m using IOAPI-3.2 to manipulate CMAQ results and other data.

And I got an issue when I used coordinate transform routines ’ LAMBERT()’

I wanted to transform Transverse Mercator ™ coordinate to longitude-latitude.

So, I made fortran scripts as below:

```
  include 'PARMS3.EXT'
  include 'FDESC3.EXT'
  include 'IODECL3.EXT'

  character(len=16) :: gname
  real :: a,b,c,xc,yc,x,y
  real :: u,v
  logical :: trmerc,trm2ll,trm2lam

  call grid_info(gname)
  if(.not.trmerc(gname,a,b,c,xc,yc)) then
     write(6,*) 'error'
  endif

  x = 197.783 ; y = 453.032
  if(.not.trm2ll(x,y,u,v)) then
     write(6,*) 'error2'
  endif

  write(6,'(a,f8.1,2x,e12.5,3f8.1/)')'a,b,c,x,y',a,b,c,xc,yc
  write(6,*) 'input x =',x,'input y=',y
  write(6,*) 'output x=',u,'output y=',v

  end

```

However, I got an error message like this:

```
0ERROR PI09Z0
LATITUDE FAILED TO CONVERGE AFTER 6 ITERATIONS

 >>--->> WARNING in subroutine LAMBERT/TRM2LL
 Projection-specific error

 a,b,c,x,y 38.0 0.10000E+01 127.0 127.0 38.0

 input x = 197.7830 input y= 453.0320
 output x= 0.0000000E+00 output y= 0.0000000E+00

```

I tried this several times and to find any problem in IOAPI Lambert.f, but I couldn’t any problem.

I want to know why I got this error and how to solve it.

I hope any ideas about this issue.

Thank you.

HyeonYeong Park