Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>Suppose this was my analysis pipeline: I want to generate 10 numbers from the normal distribution with mean <code>MU</code> and standard deviation <code>SD</code> and then do something else with them:</p> <pre><code>MU &lt;- 1 # the mean SD &lt;- .5 # standard deviation NUMBER_TO_GENERATE &lt;- 10 x &lt;- rnorm(NUMBER_TO_GENERATE, mean=MU, sd=SD) # ... more analysis here. </code></pre> <p>At the moment I copy-paste these commands into the R terminal. There are a few ways to "automate" this.</p> <h3>1. Write a function</h3> <p>I encompass my list of commands to execute into one big function, and put my parameters as function parameters:</p> <pre><code>myFunction &lt;- function( MU, SD, NUMBER_TO_GENERATE ) { x &lt;- rnorm(NUMBER_TO_GENERATE, mean=MU, sd=SD) # ... rest of analysis } </code></pre> <p>Now within R I can just do <code>myFunction(1, .5, 10)</code>, reducing the number of commands I have to type to 1.</p> <h3>2. Write a script</h3> <p>I could write a script file <code>myScript.r</code>. This is like a bash script except it's a list of R commands.</p> <p>I can <em>either</em> put my original list of commands in there, Or I could put my function in there plus an additional statement at the bottom <code>myFunction(1,.5,10)</code>.</p> <p>Then from <em>within</em> R, I can do:</p> <pre><code>source('myScript.r') </code></pre> <p>and it will run all the R commands in the script.</p> <h3>3. From the shell</h3> <p>If you want to source this script from the shell, I'd suggest having a file <code>myScript.r</code> with the function inside it.</p> <p>Then check out <a href="http://stat.ethz.ch/R-manual/R-devel/library/utils/html/Rscript.html">Rscript</a> (you can just <code>?Rscript</code> from within R). This comes installed R by default, and you use it for executing R commands from a unix/windows command line.</p> <p>For example:</p> <pre><code>[mathematical.coffee@bar ~]$ Rscript -e '1+1' [1] 2 </code></pre> <p>In particular, you could combine methods 1) and 2) with <code>Rscript</code> to do something like:</p> <pre><code>[mathematical.coffee@bar ~]$ Rscript -e 'source("myScript.R"); myFunction( 1, .5, 10 )' </code></pre> <p>to run your function. </p> <p>Or you could of course just include the <code>myFunction(1, .5, 10)</code> in your <code>myScript.R</code>, in which case you can just do <code>Rscript myScript.R</code>.</p> <p>The advantage of the former is if you wanted to do shell scripting (I only mention this because you mentioned bash scripts in your question). In a <em>bash</em> script we could do something like:</p> <pre><code>#!/bin/bash MU=1; SD=.5; NUM=10; Rscript -e "source('myScript.r'); myFunction($MU,$SD,$NUM)" </code></pre> <p>However I'd argue for not mixing bash scripts with R scripts - as I mentioned before, I only mention this option because you mentioned bash/unix scripts in your question.</p>
    singulars
    1. This table or related slice is empty.
    1. POHow to automate commands in R?
      singulars
      1. PTQuestion
    1. PTAnswer
    1. This table or related slice is empty.
    1. USmathematical.coffee
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POHow to automate commands in R?
      singulars
      1. PTQuestion
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COThankyou mathematical.coffee for providing me such a beautiful explanations.
      singulars
      1. PO
      1. USbioinformatician
    2. COWhy do advise against using R from a bash script?
      singulars
      1. PO
      1. USDunderChief
    3. CO@DunderChief I only advise against for this *particular* question, because the OP seemed a bit confused about all the options and I think one of the first two options was what they actually wanted. In general I have no issues with bash scripts and R (although I feel that you can usually achieve whatever functionality you want from the bash script, from within R (with an R script) instead).
      singulars
      1. PO
      1. USmathematical.coffee
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload