Draw paths in McIDAS

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glez_b
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Re: Draw paths in McIDAS

Post by glez_b »

I managed to draw the line in each of the points, my question now is: how to draw that line that connects each of the positions of the different events and I no connect all the dots, ie, the final product would get a figure with different trajectories of each of storms. I've been exeperimentando in McIDAS-V, but I have not managed to get the different trajectories.
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100.png
Boris_MCS
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bobc
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Re: Draw paths in McIDAS

Post by bobc »

Hi Boris -

One solution to this that I can think of is to create a separate CSV file for each storm. If you load in each one individually, the points won't connect between storms, and you should have individual storm paths/trajectories.

- Bob Carp
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bobc
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Re: Draw paths in McIDAS

Post by bobc »

Hi Boris -

It is also possible to create individual storm tracks (not connected) while keeping everything in one file. In your last image, it appears that you have the individual storms numbered (1 in the lower right, and 2 in the upper left). I created a text file where I have two tracks combined into one file, the first track includes a 1, and the second contains a 2 (file below):

201210250000 18.46 -76.391 988.9 1
201210250300 18.976 -76.22 987.2 1
201210250600 19.816 -76.327 987.6 1
201210250900 20.457 -76.082 991.7 1
201210251200 21.329 -75.563 987.9 1
201210260000 28.46 -76.391 988.9 2
201210260300 28.976 -76.22 987.2 2
201210260600 29.816 -76.327 987.6 2
201210260900 30.457 -76.082 991.7 2
201210261200 31.329 -75.563 987.9 2

I added this file through the General->Files/Directories chooser with the ‘Text Point and Trajectory Data files’ Data Type.

Point Data window defining columns in my *.txt file
Point Data window defining columns in my *.txt file


I gave a name of ‘Storm’ to the last item to distinguish between the two storm tracks. Note that I have a Pressure field included in this file, but I am not using it in the display.

In the Field Selector, I selected the Track->Storm field with the Trajectory->’Track Colored By Parameter’ Display type and clicked Create Display. This draws the whole track, but this can be changed by modifying the Visible Range in the Layer Controls tab of the Data Explorer, which controls how much of the track is visible. To display only the track for storm 1, check the checkbox for Visible Range, and change the range to From: 1 To: 1.

Setting the Visible Range to make only one of the tracks visible
Setting the Visible Range to make only one of the tracks visible


Now, only the track from storm 1 will appear. To get the track for your next storm, go back to the Field Selector and click Create Display again. This will add all of the data, but display track 2 using the same method used to display track 1, but change the Visible Range to From: 2 To: 2. Now you should have both tracks drawn individually in your display without connecting.

Final display with two individual tracks displayed. Note that there are two layers in the Legend, one for each track
Final display with two individual tracks displayed. Note that there are two layers in the Legend, one for each track


- Bob Carp
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joleenf
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Joined: Mon Jan 19, 2009 7:16 pm

Re: Draw paths in McIDAS

Post by joleenf »

Boris,

Bob's solution is really nice because the tracks are isolated by storm. Another options would be to add a missing value to the end of each storm track (see paths3.csv). In this way, the missing value can be filtered by adjusting the visible range of the track. A major disadvantage to this approach is that it adds extra points and can reduce efficiency.

See http://www.ssec.wisc.edu/mcidas/doc/mcv ... tData.html for documentation in formatting point data files.
paths3.csv
Please see
http://www.ssec.wisc.edu/mcidas/doc/mcv_guide/current/data/TextPointData.html

for point data tutorial.
(1.08 KiB) Downloaded 429 times

Screen Shot 2013-01-16 at 9.59.05 AM.png

stormtrajectory.gif


Joleen
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joleenf
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Re: Draw paths in McIDAS

Post by joleenf »

A great tip from TomW simplifies this process more. If there are missing values specified as in paths3.csv, they can be specified in the header

Code: Select all

(index)->(Event(Text),PointNo,Time,Latitude,Longitude)
Event(Text)[],PointNo[unit="degrees" missing="-9"],Time[fmt="yyyy-MM-dd HH:mm:ss"],Latitude[unit="degrees"],Longitude[unit="degrees west"]


On my mac, when a trajectory is plotted by parameter, the missing values cause breaks between the individual events without the need to adjust the visible range.

Joleen
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