Update a plot in R - r

I have an R script that takes in a dataset and a list of keywords. It then creates a plot based on how many times each of the keywords occur in the dataset, and saves it as a png image. Now, I want to make the keyword list dynamic, i.e. I want the keywords to be user inputs. Somehow, in the environment I am working in, it so happens that once the user has entered a list of keywords, I execute the R script and present the user with the plot. Now when the user enters some more keywords, they are appended to the previous list and since the complete list of keywords are sent to the R script, it performs the complete task again. It is obvious that it is doing a lot of unnecessary work of finding the keywords that were there in the first run too.
For example, in the first run, list of keywords:- "One", "Two", "Three".
In the second run, list of keywords:- "One", "Two", "Three", "Four", "Five", "Six"
In the second run, it wastes a lot of time working on keywords "One", "Two" and "Three".
Since the dataset will be huge and so will the number of keywords, it will take a lot of time to execute.
My question is, is there a way I could prevent this, retain the previous plot and modify the previous plot to present the new keywords as well?

In theory it is possible to read in a png file and use it as a background, then add additional points/lines to it, but it would be much more complicated (and probably produce much uglier results) than saving the information to create the plot and just recreating the plot from scratch.
To do this (using base graphics) you could read the existing png file using the readPNG function from the png package. Then create a new plot using plot.new and plot.window. You would then need to use par to set the plotting region to the entire device region. Then use rasterImage to plot the png file as a background. Now you need to use par again to set the plotting region and user coordinates to match the previous png plot (this could be the most complicated part and if you don't get it right then the results will be all wrong). Then you can use points and lines to add to the plot. Note that the quality of the points and labels from the first plot will probably decrease every time that you do this (a png file does not save the text, but rather information on what colors to make which pixels).
It would be better (as mentioned in the comments) to just save the information needed to create the plot, then recreate the plot with the added information.
You could also look at the ggplot2 package which stores all the information to create a plot in an object, then plots it when printed. You can add (using +) options, data, etc. to the plot information and it will take care of the replotting.

Related

Interactive plots on local .html via .rmd or Shiny

I'm trying to build a .html file via RStudio in to have following function(simplified).
plot1:a simple time series plot of $y_t$, where user can manually pull/drag each dot to change it's values a each time point.
plot2:a time series dependent on $y_t$, such as $f(y_t)=2*y_t+1$, once the value in plot1 changed, the plot2 will also change accordingly.
I want the .html self contained, not cloud based. I'm thinking of plotly, shininy/knitr, but I'm not sure if I'm in the direction or how to connect the dots. Hope anyone can point me to the right direction.
A self-contained/client-side html report sounds well-suited for flexdashboard. It's based on R Markdown, and therefore can accommodate Shiny elements.
I don't know if you can modify values with a mouse, but you can certainly modify values with sliders and other inputs, as well as have a second plot react to a first plot.
You may see some more possibilities in the gallery.

Editing multiple plots in Rstudio

One interesting feature of RStudio is it allows to save multiple plots generated from a script. This however opens up the problem of how to edit multiple plots. My issue at the moment is adding lines to histograms using the abline() function. This function was designed however to work with the last plot generated by the environment. One way of course would be ad the lines as soon as the plot is generated, however I have to calculate the coordinates at the end of the algorithm, by then I have transformed the data and generated multiple plots from it. So I was wondering if there isn't a way to tell R to search for a given plot and add the line to it. I read abline() documentation but found nothing regarding it. One can always save the data necessary to generate the plot and generate it at the end of the script, but I was wondering if there isn't a less consuming memory method.
One way to get around this issue is:
1.Save your graphics as variables, for ex: hist_1=hist(x, plot=FALSE)
2.Write any code u like, for ex: very complicated code give y as a number for output
3.plot(hist_1)
4.abline(hist_1, v=y)
gives a general idea of how to edit multiple plots without having to save multiple copies of datasets and without overloading Rstudio interface. Works well with the R ubuntu terminal too.

LocusZoom standalone change x-axis and use the plots in a script

I am using the standalone LocusZoom software,but I am having two problems:
I have to create a plot showing only position on the x-axis (not showing the genes). If I just use showGenes=FALSE with nothing else the genes still appear, but if I use rfrows=0 then the genes are not shown, but the problem is that also the x-axis label with the positions disappears. Is there a way to only show the position label? It looks like the only way to do this is to modify the original script...
Is there a way to use several plots created using LocusZoom in an R script to position many plots into one unique figure? (output is a pdf for now) There is an option listed in the LocusZoom webpage (http://genome.sph.umich.edu/wiki/LocusZoom_Standalone) called "prelude" but I cannot get more info on how to use it.
If you have any suggestions for either of these two issues it would be very helpful! Thanks!!

Graphite: multiple series with a single command

I would like to put two series in the same graph on the graphite dashboard. However, since the dashboard requires single-line commands I could not find a way that doesn't involve the use of a wildcard.
Here's an example of the two series I would like in the same graph:
sum(base.foo.bar.positive.*)
sum(base.foo.bar.negative.*)
I tried several separators but I could not get it to work. Any ideas?
You have a few options here...
Merge the 2 graphs on to the graph via the drag and drop in the dashboard
OR
Use the sumSeriesWithWildcards() function
Merge 2 or more wildcard matching
Open your first graph on the dashboard
Open your second graph on the same dashboard
Click and hold the second graph and drag it over the first graph
Use groupByNode() and wildcard matching
This is not as nice, and will not always work however you will be able to do this all in one line.
sumSeriesWithWildcards(base.foo.bar.{positive,negative}.*, 3)
This will do the following:
Select all all the graphs that match base.foo.bar.positive.* and base.foo.bar.negative.*
Sum the data by the node at position 3: positive, negative
You might want to have a read over the following page: http://graphite.readthedocs.org/en/1.0/functions.html

Repeat plot command with minor changes in R

I made a plot in R and I want to repeat all the commands (like plot(), legend() or line()) that were carried out for this plot, with some minor changes. For example I want to set the axes to logarithmic scale and change the title of the plot.
In gnuplot I would use the replot command.
plot ...
set title "The same plot with logarithmic axes"
set logscale
replot
Is something like this possible in R. The only thing that comes to my mind of doing this (besides changing the values manually and re-run the lines of codes) would be setting up a function, that asks for all parameters that might be changed by the user.
Thanks for your help,
Sven
R uses a pen and paper graphics model - once the plot has been drawn on the device that is it. If you want to change some aspect of the plot, you need to replay the graphics function calls that produce the plot with the changes made to the code.
Depending on what you are really doing there are two options:
If this is just for you, write code in a text editor / IDE that knows R and can send chunks of code at a time to R. That way the code to produce the figure is recorded in a separate script which you can paste into/send to R making the changes you need each time to the script.
If you are going to be doing this often, then write yourself a wrapper plotting function that encapsulates the plot code you want but allows you to pass in arguments to alter the aspects you want.
Lattice and ggplot2 are a little different as they are based on grid graphics and create objects that when printed produce a plot on the device. One can manipulate that object to alter what is drawn, and with grid one can push and pop things on to / off a viewport.

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