Hourly pressure change.

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ClintF
Junior Member
Posts: 8
Joined: Mon Jan 10, 2005 4:58 pm
Location: Memphis TN

Hourly pressure change.

Post by ClintF »

Good day.
I am trying to get a chart that shows the pressure change between two consecutive hours with positive numbers blue and negative numbers in red and max and min points. The desired end result would be a chart that shows just the pressure change. But the slpr for the current hour is drawn also. How do I get the script to plot just the pressure change.

The following is the script I have come up with.
download,http://weather.cod.edu/digatmos/sao/@Y@ ... c:\Program files\DigitalAtmosphereWS\data\temp.dat
ingest,c:\Program files\DigitalAtmosphereWS\data\temp.dat
analyze,stor=1 cont slpr hsfc
erase
download,http://weather.cod.edu/digatmos/sao/@Y@ ... c:\Program files\DigitalAtmosphereWS\data\temp.dat
ingest,c:\Program files\DigitalAtmosphereWS\data\temp.dat
analyze,stor=2 cont slpr hsfc
erase
analyze,mxmn cont cint=4 line=2 color=0:0:180 grtn=0 cont cint=4 line=2 color=200:0:0 lstn=0 sdif=1:2

Thank you
Fred
Senior Member
Posts: 198
Joined: Tue Nov 25, 2003 4:22 pm
Location: Suoi Tien, Vietnam

Post by Fred »

Hello

Very nice script. The $H is new for me. I could not find it in the manual (but it's rather early here).
When I run the script I get 1 long line and 2 short + some X and N. I don't see the SLPR. Only when I add a space after the second erase I see a lot of lines. Is this what you mean? Can you place a map on the forum or send it to me? Then I know exactly what you have.

Greetings

Fred
texsky
Senior Member
Posts: 172
Joined: Fri Dec 12, 2003 9:42 pm

Post by texsky »

To my knowledge, manipulations across different data files are not possible, so the only way to plot pressure tendency is to extract it from the synoptic observations.

I could be wrong though, you may want to ask Tim about it.

Bob
ClintF
Junior Member
Posts: 8
Joined: Mon Jan 10, 2005 4:58 pm
Location: Memphis TN

Post by ClintF »

The $h is for the last hours data.

Bob, I think this script makes it possible to plot pressure changes between two consecutive hours. As of yet, I have not verified the results but am just testing it. Any feed back is welcome.
I would like to post the results but am not able to get them to show up here.
Thanks
Fred
Senior Member
Posts: 198
Joined: Tue Nov 25, 2003 4:22 pm
Location: Suoi Tien, Vietnam

Post by Fred »

Just a quick reaction before I go to my work. My first results looks very good, although not tested in detail. I made one with coloured bands, only the negative is not good yet. Later more with the whole script.

Greetings

Fred
Fred
Senior Member
Posts: 198
Joined: Tue Nov 25, 2003 4:22 pm
Location: Suoi Tien, Vietnam

Post by Fred »

Tim

Trying to modify the above script I faced again the problem of the negative values.
Using the command "..... equa=-2 sdif=1:2" does not give a result. I tried the command in a lot of different ways but nothing works. To be sure, is it a bug in the program or do I make mistakes in the syntax?

Although adding a value to it and ask for the positive value works sometimes it often causes other problems and makes the script very complex. I (and many others) hope that -if it is a bug- it can be solved in the next release.

Greetings

Fred
ClintF
Junior Member
Posts: 8
Joined: Mon Jan 10, 2005 4:58 pm
Location: Memphis TN

Post by ClintF »

Tim, thanks for the help.

I have been looking at the results and overall it looks promising. The positive side looks the best and I agree that the negative side looks suspect. I would be intrested in seeing your modifications to the script to see how you did it.

I did have a space after the second erase.
Thanks again.
Fred
Senior Member
Posts: 198
Joined: Tue Nov 25, 2003 4:22 pm
Location: Suoi Tien, Vietnam

Post by Fred »

Hello

I continued testing my script and I found some more strange things.
For a value 2 the command GRTN=1 gives the requested colour, while EQUA=2 gives a white fill: nothing happens!
Or the EQUA command does not work or asking =2 is perhaps not correct. This also because of the second problem. If I ask LSTN=0 I expect everything starting with -1. I also get 0. Looking to the N I can see a "-0" displayed in it. But as I stated in my previous post, asking for - does not work.

What now??

Greetings

Fred
Guest

Post by Guest »

The last time I ran the script I looked at stor=1 and compared it to stor=2 and they were the same. :?: :?:
Then I took it apart and ran each part seperaty. Past hours data was saved all right and was correct. The current hours data also was saved corectly. I plotted one over the other and then ran the third part, the sdif=1:2. I devided the result into three parts and then contured each part seperately. This result was the isopleths were reversed those that were lstn=0 were plotted where the grtn=0 was supposed to be and visa-versa. This was confermed I contured equa=0 in a third color. Both sides plotted the 0 line. What I do not know is if the program findes the differance graphicly or mathamaticly, or it just does not know what to do.
I was wondering if sdif=2:1 would work.

I do not know what is going on with this and hopeing that Tim might beable to give some insites to the problem.

:idea: An idea just accured to me to runit with temperatures and see what happens. I will let you know.
ClintF
Junior Member
Posts: 8
Joined: Mon Jan 10, 2005 4:58 pm
Location: Memphis TN

Post by ClintF »

Every time I run this script I get a different results. I think there is a bug in the program. I am going to put this on the back burner for now.
Thanks for the help.

I was the "Guest" for the last post.
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