Dear All,
Thank you for your advice.
I have looked at the plotrix package and with what I gathered, I
tinkered with the code below and obtain the attached graph:
oolt<-read.table("QUERY2",col.names=c("Lat","Lon"))
latlim<-c(20,45)
lonlim<-c(-180,180)
latbreaks<-seq(latlim[1],latlim[2],by=5)
lonbreaks<-seq(lonlim[1],lonlim[2],by=10)
mids<-function(x) {
lenx<-length(x)
return((x[1:(lenx-1)]+x[2:lenx])/2)
}
lonmids<-mids(lonbreaks)
latmids<-mids(latbreaks)
oolt$loncuts<-cut(oolt$Lon,lonbreaks)
oolt$latcuts<-cut(oolt$Lat,latbreaks)
counts<-table(oolt$latcuts,oolt$loncuts)
png("test.png")
library(plotrix)
countcol<-color.scale(counts,extremes=c("blue","red"))
library(maps)
map("world",xlim=c(-180,180),ylim=c(20,45))
w = map("world")
for(lon in 1:length(lonmids)) {
for(lat in 1:length(latmids)) {
if(counts[lat,lon] > 0)
draw.circle(lonmids[lon],latmids[lat],radius=sqrt(counts[lat,lon]),
border=countcol[lat,lon],col=countcol[lat,lon])
}
}
box()
axis(1)
axis(2)
x<-seq(-180,180,30)
y<-seq(-90,90,30)
nx = 12
ny = 6
grid(nx,ny,col =
"red",lty="dotted",lwd=par("lwd"),equilogs=TRUE)
testcol<-color.gradient(c(10,30),0,c(30,10),nslices=5)
color.legend(-180,-130,100,-150,countcol,testcol,gradient="x")
I now have the horizontal color legend.
But I have two major problems still.
(1) The black line on top of the color bar is meaningless and I want it go.
(2) I want the numerical values plotted to appear on the color bar
(see the color.legend.png attached please) such that it can be used to
interpret the map.
I would be most grateful for any further assistance.
Very best wishes
Ogbos
On Tue, Dec 11, 2018 at 11:14 AM Jim Lemon <drjimlemon at gmail.com>
wrote:>
> Hi Ogbos,
> I have been off the air for a couple of days. Look at the color.legend
> function in the plotrix package.
>
> Jim
> On Tue, Dec 11, 2018 at 12:39 PM Ogbos Okike <giftedlife2014 at
gmail.com> wrote:
> >
> > Dear Jim,
> > I am still having trouble with the colour code. I await your help when
> > you are less busy.
> >
> > Thank you.
> > Best
> > Ogbos
> > On Mon, Dec 10, 2018 at 6:25 AM Ogbos Okike <giftedlife2014 at
gmail.com> wrote:
> > >
> > > Dear Jim,
> > >
> > > I used a bit of my data in my attempt to follow the code.
> > >
> > > I got the attached plot after some tweaks.
> > >
> > > I would like to add horizontal color bar legend that could be
used to
> > > explain the number of lightning counts at different points on the
> > > latitude band as plotted.
> > >
> > > Thank you
> > > Warm regards
> > > Ogbos
> > >
> > > On Sun, Dec 9, 2018 at 9:46 PM Jim Lemon <drjimlemon at
gmail.com> wrote:
> > > >
> > > > Hi Ogbos,
> > > > Here is a slight modification of a method I use to display
trip
> > > > density on a map:
> > > >
> > > > oolt<-read.table(text="Lat Lon
> > > > 30.1426 104.7854
> > > > 30.5622 105.0837
> > > > 30.0966 104.6213
> > > > 29.9795 104.8430
> > > > 39.2802 147.7295
> > > > 30.2469 104.6543
> > > > 26.4428 157.7293
> > > > 29.4782 104.5590
> > > > 32.3839 105.3293
> > > > 26.4746 157.8411
> > > > 25.1014 159.6959
> > > > 25.1242 159.6558
> > > > 30.1607 104.9100
> > > > 31.4900 -71.8919
> > > > 43.3655 -74.9994
> > > > 30.0811 104.8462
> > > > 29.0912 -85.5138
> > > > 26.6204 -80.9342
> > > > 31.5462 -71.9638
> > > > 26.8619 97.3844
> > > > 30.2534 104.6134
> > > > 29.9311 -85.3434
> > > > 26.1524 159.6806
> > > > 26.5112 158.0233
> > > > 26.5441 158.0565
> > > > 27.8901 -105.8554
> > > > 30.3175 104.7135
> > > > 26.4822 157.6127
> > > > 30.1887 104.5986
> > > > 29.5058 104.5661
> > > > 26.4010 157.5749
> > > > 30.2281 104.7585
> > > > 31.4556 110.5619
> > > > 30.1700 104.5861
> > > > 26.3911 157.4776
> > > > 30.6493 104.9949
> > > > 30.2209 104.6629
> > > > 26.0488 97.3608
> > > > 30.2142 104.8023
> > > > 30.1806 104.8158
> > > > 25.2107 160.1690
> > > > 30.6708 104.9385
> > > > 30.4152 104.7002
> > > > 30.2446 104.7804
> > > > 29.5760 -85.1535
> > > > 26.4484 92.4312
> > > > 26.3914 157.4189
> > > > 26.3986 157.4421
> > > > 30.4903 -88.2271
> > > > 30.6727 104.8768
> > > > 30.2518 104.6466
> > > > 41.6979 -78.4136
> > > > 33.7575 72.1089
> > > > 26.8333 -80.9485
> > > > 25.3103 124.0978
> > > > 30.1742 104.7554
> > > > 30.6345 104.9739
> > > > 30.2075 104.7960
> > > > 30.2226 104.7517
> > > > 30.5948 105.0532",
> > > > header=TRUE)
> > > > latlim<-c(20,45)
> > > > lonlim<-c(-90,160)
> > > > latbreaks<-seq(latlim[1],latlim[2],by=5)
> > > > lonbreaks<-seq(lonlim[1],lonlim[2],by=10)
> > > >
> > > > mids<-function(x) {
> > > > lenx<-length(x)
> > > > return((x[1:(lenx-1)]+x[2:lenx])/2)
> > > > }
> > > > lonmids<-mids(lonbreaks)
> > > > latmids<-mids(latbreaks)
> > > > oolt$loncuts<-cut(oolt$Lon,lonbreaks)
> > > > oolt$latcuts<-cut(oolt$Lat,latbreaks)
> > > > counts<-table(oolt$latcuts,oolt$loncuts)
> > > > library(plotrix)
> > > >
countcol<-color.scale(counts,extremes=c("blue","red"))
> > > > map("world",xlim=c(-90,160),ylim=c(20,45))
> > > > for(lon in 1:length(lonmids)) {
> > > > for(lat in 1:length(latmids)) {
> > > > if(counts[lat,lon] > 0)
> > > >
draw.circle(lonmids[lon],latmids[lat],radius=sqrt(counts[lat,lon]),
> > > > border=countcol[lat,lon],col=countcol[lat,lon])
> > > > }
> > > > }
> > > >
> > > > If you have very large counts in some places you may need to
adjust
> > > > the radius of the circles.
> > > >
> > > > Jim
> > > > On Mon, Dec 10, 2018 at 2:50 AM Ogbos Okike
<giftedlife2014 at gmail.com> wrote:
> > > > >
> > > > > Dear Contributors,
> > > > >
> > > > > I have a data of the form:
> > > > > Lat Lon
> > > > > 30.1426 104.7854
> > > > > 30.5622 105.0837
> > > > > 30.0966 104.6213
> > > > > 29.9795 104.8430
> > > > > 39.2802 147.7295
> > > > > 30.2469 104.6543
> > > > > 26.4428 157.7293
> > > > > 29.4782 104.5590
> > > > > 32.3839 105.3293
> > > > > 26.4746 157.8411
> > > > > 25.1014 159.6959
> > > > > 25.1242 159.6558
> > > > > 30.1607 104.9100
> > > > > 31.4900 -71.8919
> > > > > 43.3655 -74.9994
> > > > > 30.0811 104.8462
> > > > > 29.0912 -85.5138
> > > > > 26.6204 -80.9342
> > > > > 31.5462 -71.9638
> > > > > 26.8619 97.3844
> > > > > 30.2534 104.6134
> > > > > 29.9311 -85.3434
> > > > > 26.1524 159.6806
> > > > > 26.5112 158.0233
> > > > > 26.5441 158.0565
> > > > > 27.8901 -105.8554
> > > > > 30.3175 104.7135
> > > > > 26.4822 157.6127
> > > > > 30.1887 104.5986
> > > > > 29.5058 104.5661
> > > > > 26.4010 157.5749
> > > > > 30.2281 104.7585
> > > > > 31.4556 110.5619
> > > > > 30.1700 104.5861
> > > > > 26.3911 157.4776
> > > > > 30.6493 104.9949
> > > > > 30.2209 104.6629
> > > > > 26.0488 97.3608
> > > > > 30.2142 104.8023
> > > > > 30.1806 104.8158
> > > > > 25.2107 160.1690
> > > > > 30.6708 104.9385
> > > > > 30.4152 104.7002
> > > > > 30.2446 104.7804
> > > > > 29.5760 -85.1535
> > > > > 26.4484 92.4312
> > > > > 26.3914 157.4189
> > > > > 26.3986 157.4421
> > > > > 30.4903 -88.2271
> > > > > 30.6727 104.8768
> > > > > 30.2518 104.6466
> > > > > 41.6979 -78.4136
> > > > > 33.7575 72.1089
> > > > > 26.8333 -80.9485
> > > > > 25.3103 124.0978
> > > > > 30.1742 104.7554
> > > > > 30.6345 104.9739
> > > > > 30.2075 104.7960
> > > > > 30.2226 104.7517
> > > > > 30.5948 105.0532.
> > > > > The record is for lightning flashes in the continental
U.S. and
> > > > > surrounding waters within the latitudinal band between
> > > > > 258 and 458N.
> > > > >
> > > > > I want to display the result in x-y co-ordinate plot.
However, the
> > > > > data is very large such that when plotted, everything
just appeared
> > > > > blurred.
> > > > >
> > > > >
> > > > > Is there a way of using color codes to indicate the
regions of higher
> > > > > or lower flash densities?
> > > > >
> > > > > I can attach the plot I generated but I am not sure if
the moderator
> > > > > will allow it to go with this.
> > > > >
> > > > > I will send it in a separate email if required.
> > > > >
> > > > > Thank you so much for sparing your time.
> > > > >
> > > > > Best
> > > > > Ogbos
> > > > >
> > > > > ______________________________________________
> > > > > R-help at r-project.org mailing list -- To UNSUBSCRIBE
and more, see
> > > > > https://stat.ethz.ch/mailman/listinfo/r-help
> > > > > PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> > > > > and provide commented, minimal, self-contained,
reproducible code.
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Hi Ogbos,
Back on the air after a few days off. I don't have your data ("QUERY
2"), but I think this will fix your problem.
library(maps)
map("world")
box()
library(plotrix)
color.legend(-180,-150,100,-130,legend=c(0,25000,50000,75000,100000),
rect.col=color.scale(1:5,extremes=c("blue","red")),gradient="x")
Notice that I have swapped the "yb" and "yt" values so that
they are
in increasing order. If they are reversed, the numbers will appear
within the color bar. Also you don't need to call color.gradient, just
pass the output of a five increment color scale from blue to red (or
whatever you like) to the rect.col argument.
Jim
Ogbos Okike
2018-Dec-14 11:38 UTC
[R] Plotting Very Large lat-lon data in x-y axes graph: SOLVED
Dear Jim,
Good news to me!! Welcome.
I am fine. The code elegantly displayed the color.
I also tried to adjust the line:
draw.circle(lonmids[lon],latmids[lat],radius=sqrt(counts[lat,lon])/100,
border=countcol[lat,lon],col=countcol[lat,lon]) in order to reduce
the radius of the circle in order to plot the whole data.
I am really really grateful. I will immediately include the result in
a draft manuscript to Astrophysical Journal.
With the warmest regards
Ogbos
On Thu, Dec 13, 2018 at 9:04 PM Jim Lemon <drjimlemon at gmail.com>
wrote:>
> Hi Ogbos,
> Back on the air after a few days off. I don't have your data
("QUERY
> 2"), but I think this will fix your problem.
>
> library(maps)
> map("world")
> box()
> library(plotrix)
> color.legend(-180,-150,100,-130,legend=c(0,25000,50000,75000,100000),
>
rect.col=color.scale(1:5,extremes=c("blue","red")),gradient="x")
>
> Notice that I have swapped the "yb" and "yt" values so
that they are
> in increasing order. If they are reversed, the numbers will appear
> within the color bar. Also you don't need to call color.gradient, just
> pass the output of a five increment color scale from blue to red (or
> whatever you like) to the rect.col argument.
>
> Jim
Dear Jim, Attached is a plot generated by the code for one year lightning data. Instead of lightning flashes happening randomly at all points over the globe, there is a kind of constraint making lightning to be aligned straight on the longitudes. I suspect the problem is coming from seq function in the code: latbreaks<-seq(latlim[1],latlim[2],by=2) lonbreaks<-seq(lonlim[1],lonlim[2],by=10). I tried to remove them but found it difficult. Part of the data (see below) shows that lightning happens at all latitudes and longitudes and as such, cannot be plotted to appear only on straight lines: 0.8312 95.2156 -3.3851 -65.3236 -3.2696 -65.2364 -3.2679 -65.2349 -17.6404 164.7025 -4.8285 148.8214 2.6477 -67.6568 -0.2350 -73.4833 -16.8655 40.9587 8.1179 -61.6474 -0.2755 93.3401 -17.1733 119.9011 1.1245 -69.7640 -20.0035 -149.3088 -3.4200 177.8753 3.0133 -67.5590 15.4684 -21.9331 -17.6166 120.2656 -17.3888 165.9368 -17.6953 164.7335 -1.8623 -74.0017 -3.3562 -71.1195 -11.5775 130.1496 -11.5720 130.4004 18.7159 -21.0251 -9.3788 -75.0815 -2.8341 -71.9095 -2.8276 -71.9380 -19.0845 166.5715 1.3692 -69.8615 1.0989 -69.8881 1.0351 -69.9390 1.3306 -69.9484 13.4238 -83.6240 -18.2490 165.4406 2.8831 -67.6648 3.0405 -67.4912 1.2068 -70.0177 -34.6024 -67.2998 -8.6378 -46.0881 -17.7834 119.7202 2.5582 -69.4447 -6.8894 -47.9581 -16.6939 40.7143 1.4648 -69.7636 4.5290 -62.5343 4.6965 -62.6023 -18.9731 166.2414 -3.6024 173.9586 -3.4901 173.8333 -3.8061 -176.4053 -16.7814 -53.0986 -0.6284 -70.7341 -3.1878 -71.8722 -4.3205 176.7693 -4.3616 176.8269 -16.8295 119.7462 2.1829 -62.9190 -16.6656 42.0181 3.5589 -61.7756 1.3026 -69.9409 33.3995 13.4344 3.0125 -67.6869 3.0155 -67.7028 -7.3156 -48.0353 -17.5709 164.6291 33.0699 14.3376 -5.6291 -48.6772 -2.8796 -71.8747 -2.6448 -71.5548 -3.0977 -71.5027 1.1513 -69.8094 1.1024 -69.8070 -3.6739 -65.2433 25.9860 -51.3312 26.0156 -51.4377 -6.1894 -56.5574 3.2794 95.4703 18.6850 -20.8606 2.8957 -68.6864 1.0930 -69.7733 1.4467 -69.7631 -17.8441 27.0904 1.4039 -69.9049 0.9384 -69.8649 -2.2356 170.8400 2.7273 -67.6561 5.2676 -62.7957 -16.9645 119.2204 33.2544 13.6508 -6.8735 -48.0914 -17.5725 120.1941 10.8718 -59.0204 1.9115 -62.8357 2.4337 -4.8253 -17.2323 119.7706 -7.4806 -47.9645 -13.0036 166.4029 -16.6861 -53.0932 -17.5506 164.3730 2.2578 158.9620 -2.9222 177.1345 5.2906 -62.6111 5.0903 -62.5855 2.2920 91.7130 -6.2985 -55.5143 2.9048 -67.6558 3.0313 -67.6569 -1.5240 -71.0068 1.4910 -69.3833 3.0779 -67.7509 2.8380 -67.7203 Thanks for more inputs. Ogbos On Thu, Dec 13, 2018 at 9:04 PM Jim Lemon <drjimlemon at gmail.com> wrote:> > Hi Ogbos, > Back on the air after a few days off. I don't have your data ("QUERY > 2"), but I think this will fix your problem. > > library(maps) > map("world") > box() > library(plotrix) > color.legend(-180,-150,100,-130,legend=c(0,25000,50000,75000,100000), > rect.col=color.scale(1:5,extremes=c("blue","red")),gradient="x") > > Notice that I have swapped the "yb" and "yt" values so that they are > in increasing order. If they are reversed, the numbers will appear > within the color bar. Also you don't need to call color.gradient, just > pass the output of a five increment color scale from blue to red (or > whatever you like) to the rect.col argument. > > Jim-------------- next part -------------- A non-text attachment was scrubbed... Name: testB2.png Type: image/png Size: 107473 bytes Desc: not available URL: <https://stat.ethz.ch/pipermail/r-help/attachments/20181214/c584bd3d/attachment.png>