NAME:
x111disprange - display a range of time vs frq maps.
SYNTAX: img=x111disprange(freqLow,freqHi,day=day)
ARGS:
freqLow: float. first freq in Mhz.
freqHi : float. last freq in Mhz.
KEYWORDS:
day : int. data to disp. default:0
0 - 30nov00
1 - 02dec00
2 - 03dec00
3 - 16nov01 sbwide only
DESCRIPTION:
The x111 rfi monitoring cycles through the frequency range of all receivers
(327 through cband) looking at the rfi. At each frequency setting,
60 1 second integrations are recorded. The correlator is configured as
4 sbc of 25Mhz bw with 1024 channels (receivers < 25 Mhz bw use narrower
settings). With this setup 100 Mhz can be covered each minute. It takes
51 steps to cover all of the receivers.
For a particular frequency step there will be 60 1 second records followed
by another 60 1 second records about 1 hour later.
The center frequencies of each band are:
RCVR FreqRange steps bw/img Notes
327 251-320 1 25. polB has a narrow filter
430 418 1 25. no data yet (rcvr down).
610 612 1 12.5
lbw 1111-1824 8 25
lbn not monitored..
sbw 1761-3118 15 25. no data yet (rcvr down).
sbn 2334-2403 1 25.
cband 3961-6146 24 25.
Data was acquired on 30nov00, 02dec00, 03dec00 running about 12 hours per
night. This routine will display a set of 25 Mhz images (one at a time). The
user specifies the date to use via the day keyword (default is 30nov00).
The frequency low/high parameters specify the frequency range to display.
Any image that falls within this range will be displayed.
Processing of images:
An image consists of a 25 Mhz frequency chunk by 1 second integrations.
Each group of 60 records are taken consecutively. A group is normalized
to the median bandpass of the group. Adjacent groups are spaced by about
1 hour. The division by the bandpass makes the image units Tsys.
Histogram equalization will arrange the data values so that there are an
equal number of pixels in each of the 256 greyscale values. This gives
maximum contrast but the lookup ramp is not linear in power (the profile
and readback values are of the original linear data in units of Tsys). h-
(described below) turns off histogram equalization giving a linear ramp
max to min). PolA was used for the current set of images.
EXAMPLE:
1. Before you run this the first time in an idl session:
- idl
- if you don't already have phils idl path in your startup file you
need to enter @phil
- @x111init .. load in the procedures to use.
- window,3,colors=256 .. this guarantees 256 colors for the image.
2. img=x111disprange(1000,2000) .. disp 1000 through 2000 Mhz day 0.
This displays the first image and the line:
q-quit,h-:histeq,n:nextimg,b:backimg,r-:rdpix,p-:profiles:
These are the choices you have. You may have to put the cursor in this
window to get a reply:
q : quit the display
h(-) : histogram equalize the display. h- will turn it off. The
default is histogram equalization.
return: or
n : move to next image
b : move back to previous image.
r(-) : turn on/off pixel readback. When on, the image pixel coordinates
0-(xdim-1),0-(ydim-1), and pixel value are displayed. Clicking
the left button outputs a fresh line (to record a value). Clicking
the right button (in the image window) stops the display. When
this is on, no other commands can be entered.
p- : Turn profiles on or off. A 2nd window is displayed with a
horizontal or vertical cut through the image. The left mouse
button toggles between horizontal and vertical. The right mouse
button stops the profiling. No other commands can be entered while
profiling is on.
3. Stopping.
The loop will stop when you increment beyond the end of the list with
n or you enter q. The current image will be returned as a float
array in the variable img.You can use the indices from (r) to
process a particular strip. Suppose r returned x=215,y=20.
You could then look at the vertical line x=215 or the horizontal line
y=20 with:
dv=reform(img[215,*])
plot,dv
dh=img[*,20]
plot,dh
AFter quiting xloadct allows you to manipulate the color of the
last image displayed.
GOTCHAS:
The following problems will someday be fixed by me.
1. If you turn on p, or r, you need to turn them off before you can
enter any more commands.
2. You need to move the cursor to the text window for the ascii commands
to be accepted. You must be in the image window for p,r to update.
3. The p display should allow you to scale the plot.
4. xloadct cannot modify the lookup table while you run this
routine (although after quitting, the last image can be played with).
(See /pkg/rsi/local/libao/phil/Cor2/x111/x111disprange.pro)