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20010304: graphic line width/dash pattern; proftomd decoding (cont.)

>From: "Paul L. Sirvatka" <address@hidden>
>Organization: College of DuPage
>Keywords: 200102162013.f1GKD9L01250 McIDAS-X SFCCON GRDDISP

re: conversion of BATCH file to McBASI script
>I will look into that if time permits.

Like most things, the first time you do this will be the hardest.

re: calculating relative humidity for upper air data
re: I will have to see if there is an easier way to do this.
>Thanks!

It strikes me that there must be an easier way, but I havn't been able
to find the routine that does the calculation.

re: use ZA instead of FRMLABEL to label entire frame
>Yes that worked! It was in the help for ZA...just not SHOWVG. Sorry.

re: plotting shear vector
>Is this possible?

It should be.

re: UNIT of KTS incorrect
>Sorry again. I figured it out right after I sent it.  The KTS was a
>mistake.Thanks for catching it.

No biggie.

re: use string instead of value of string for contour levels
>Crap! So easy but I could not see it.

I know what you mean.  The easiest things turn out to be the hardest to
find especially after looking at the problem for a long time.

>OK Here is a bug that has caused me sleepless nights (only because I was
>up late working on it)
>
>Here is a test program
>
>REM IGU DEL 21
>ERASE F 1 11 PAN=1 4
>
>REM For US use SURFACEMAP, for Canada use UCANADAMAP
>REM For Southern and Northern Plains use USPLNSMAP and UNPLNSMAP
>REM For floater choose from : MIDWEST, GLAKES, NEWENGLAND, SOPLNS, NOPLNS
>REM                           WEST, SOUTHWEST, or GULFCOAST
>
>TE UBASEMAP "GULFCOAST
>
>REM SFC-500 MB Shear; Total Totals
>PANEL 2 2 10 10
>
>REM Create Total Totals in gridfile 23
>IGU DEL 23
>RAOBCON T 500 #UBASEMAP OUT=SAVE MYDATA/GRIDS.23
>RAOBCON T 850 #UBASEMAP OUT=SAVE MYDATA/GRIDS.23
>RAOBCON TD 850 #UBASEMAP OUT=SAVE MYDATA/GRIDS.23
>
>GRDDISP MYDATA/GRIDS.23 10 MAP=#UBASEMAP GRID=1 OUT=PLOT PANEL=1 FORMAT=I3
>PIN=2 2
>GRDDISP MYDATA/GRIDS.23 10 MAP=#UBASEMAP GRID=2 OUT=PLOT PANEL=2 FORMAT=I3
>PIN=2 2
>GRDDISP MYDATA/GRIDS.23 10 MAP=#UBASEMAP GRID=3 OUT=PLOT PANEL=3 FORMAT=I3
>PIN=2 2
>RAOBPLOT T 500 #UBASEMAP PANEL=4 COLOR=4
>
>TE TT "44 48 52 56 60 64
>GRDDISP MYDATA/GRIDS.23 10 MAP=#UBASEMAP G1='PARAM T; GRID 1' G2='PARAM
>T;GRID 2' G3='PARAM TD; GRID 3'
>NEWPAR=TT T 500 MATH='G2+G3-2*G1' FORMAT=I3 OUT=CON COLOR=3 CINT=TT
>DASH=ALL PANEL=4
>
>This program plots out the grid points for calculating the Total
>Totals. It works fine except, when I use the GULFCOAST map (not TX or some
>others) it does not wirk properly.

Hmm... this is definitely an artifact of the contouring algorithm (it
is a classic kind of problem, by the way).  In order to minimize edge
effects, it is best to create the grids on a region that includes as
much of the observational data as possible.  For instance, you could
replace the #UBASEMAP in the RAOBCON invocations with NA (North America
in MERCator projection).  Leave the GRDDISP plotting region as you
specified it above:

TE UBASEMAP "GULFCOAST

REM SFC-500 MB Shear; Total Totals
PANEL 2 2 10 10

REM Create Total Totals in gridfile 23
IGU DEL 23
RAOBCON T 500 NA OUT=SAVE MYDATA/GRIDS.23
RAOBCON T 850 NA OUT=SAVE MYDATA/GRIDS.23
RAOBCON TD 850 NA OUT=SAVE MYDATA/GRIDS.23

GRDDISP MYDATA/GRIDS.23 10 MAP=#UBASEMAP GRID=1 OUT=PLOT PANEL=1 FORMAT=I3 
PIN=2 2
GRDDISP MYDATA/GRIDS.23 10 MAP=#UBASEMAP GRID=2 OUT=PLOT PANEL=2 FORMAT=I3 
PIN=2 2
GRDDISP MYDATA/GRIDS.23 10 MAP=#UBASEMAP GRID=3 OUT=PLOT PANEL=3 FORMAT=I3 
PIN=2 2
RAOBPLOT T 500 #UBASEMAP PANEL=4 COLOR=4

TE TT "44 48 52 56 60 64
GRDDISP MYDATA/GRIDS.23 10 MAP=#UBASEMAP G1='PARAM T; GRID 1' G2='PARAM T;GRID 
2' G3='PARAM TD; GRID 3' NEWPAR=TT T 500 MATH='G2+G3-2*G1' FORMAT=I3 OUT=CON 
COLOR=3 CINT=TT DASH=ALL PANEL=4

If you do this and then look at the grid point values, you will see
that they match your expectations.

>GULFCOAST OUTLINEFILE=   OUTLUSAM \
>       MCOLOR=        8 \
>       PROJECTION=   CONF \
>       LAMB_CONF_SC= 'LAT=24 39 LON=78 105 SLON=91'
>THis is defined in the MAP.SITE

OK, I used this also.

>Although the coldest temp around MAF is -25 the grid insists that a grid
>point on that site should be -28...thereby overdoing the TT by 6 degrees.

Yes, I see what you are referring to.

>It is a very subtle problem...and as I said when I use another map the
>grid point is different. I do not know how it puts a 500 T so much colder
>than any real data point around it.

Again, I am pretty sure that you are seeing an edge effect of the
objective analysis routine.

>Maybe it is not abig deal, but it scares me in using other things.

Objective analyses are tricky things, especially in data sparce regions
like for upper air obs.  It is most likely that one or more of the
upper air values that are left out of the objective analysis in the
GULFCOAST region is(are) the determining values.

>BTW 12Z data on March 4.

I used this in my tests of your BATCH file.

>You do not have to "fix" anything but it is a heads up for a weird event.

Actually, I don't think that there is anything to fix in the TT
calculation BATCH file.  I have, however, been able to reproduce
something that you reported previously:  if I am looking at frame 10
when the above BATCH file runs, I get a floating point error, and the
session gets blown away.  This is a very strange problem, and one that
definitely warrents investigation.

Tom