This code snippet determines the day of the week associated with a date. The class method "test" takes a date as a string in "mm/dd/yyyy" format, and returns an integer corresponding to a day of the week:

Class cartertiernan.getDayfromDate Extends %RegisteredObject
{
    classmethod test(date) as %Integer {
        //Set date = $ZDATE(date) //  Looks like: mm/dd/yyyy
     
        Set monthList = $LISTBUILD(0,3,3,6,1,4,6,2,5,0,3,5) // (Jan,Feb,Mar,Apr,...)
        Set centuryList = $LISTBUILD(6,4,2,0) // first two digits divisiable by 4, then subsequent centuries. EX (2000, 2100, 2200, 2300)
        Set dayList = $LISTBUILD("Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday") // Index goes from 0-6
         
        Set day = $PIECE(date,"/",2) // get the day 
        Set monthVal = $LIST(monthList,($PIECE( date,"/",1 ))) // get the month value
        Set first2DigsYear = $PIECE( date,"/",3 ) \ 100 // get the last 2 digits of the year
        Set last2DigsYear = $PIECE( date,"/",3 ) # 100 // get the first 2 digits of the year
         
        // Used for DEBUG perpouses
        /*write !,"day: ",day
        write !,"Month: ",monthVal
        write !,"last2: ",last2DigsYear
        write !,"first2: ",first2DigsYear
        write !,"cen Val: ",$LIST(centuryList,(first2DigsYear # 4) + 1),!!*/
         
        // Look here for formula explination (its the "Basic method for mental calculation")
        // http://en.wikipedia.org/wiki/Determination_of_the_day_of_the_week
        Set dayOfWeekVal = ( day + monthVal + last2DigsYear + (last2DigsYear\4) + $LIST(centuryList,(first2DigsYear # 4) + 1 ) ) # 7
     
        Quit dayOfWeekVal
    }
}

Here's a link to the code on GitHub

(originally posted to CODE by Carter Tiernan, 6/18/14)

Hi Dev Community members,

In this post, we would like to show you how to use DC tags. Let's make the most of this Developer Community option!

Sometimes I observe people scrolling manually down to the bottom of the Console Log document when they want to see the most recent messages. So I want to draw attention to the handy link that does the job for you in a single click:

This post is meant to provide a quick possible explanation for a very perplexing problem.

Scenario: You’ve just created your own administrative user in your 2014.1 (or later) instance of Caché. You gave it every possible security role (including %All), so it should in theory be able to do anything within the instance.

You’ve written a very advanced routine with a break command in it for debugging:

InterSystems FAQ rubric

Properties defined in list collections (Property XXX As list of %String;) can be manipulated using SQL functions: $LISTBUILD(), $LISTFROMSTRING().

For each SQL function, please refer to the document page below.

I'm sure most of you have already familiar with the possibility of using GZIP in InterSystems products. But, the problem is that GZIP working only with one file or stream, and it does not support folders. When you work in Unix systems, there is a possibility how to solve it, using tar compress tool which goes with every Linux system from out of the box. But what to do if you have work on Windows as well, which does not have it.

I am pleased to offer you my new project isc-tar, which will help you do not care about operating system, and deal with tar files anywhere.

InterSystems FAQ rubric

The one question that some of you might have is:

How do I change my login information for Cache Studio if I clicked the checkbox to automatically save my login info so I do not have to enter my username/password every time I open Studio?

Well.....excellent question!!!!!!

Here's the answer:

Sometimes you can face the situation when you did update the web app on Caché server but you cannot get the newest version of the app in a browser.

Here are couple recipes which help me to solve it. From simplest to more sophisticated and not obvious.

1. Refresh page in a browser

In Chrome it is Ctrl+R or 'Refresh' button. Obvious, but helpful.

2. Hard reset in a browser

If you are in Chrome, open Developer tools

InterSystems FAQ rubric

This error occurs when an instance of the class is already open at compile time.

There are two ways to deal with this issue:

1. Terminate the process or application that has the instance open
2. Compile options in the studio build menu: Check the compile flag “Compile classes in use” and compile.

If you want to determine which process is using the class, try the sample routine below.

Checking if Directory or File Exists:

Outlined below is an example of how to check if a directory exists:

Set directoryName="c:\temp\nosuchdir"

/* Check for existence of a directory - Return Value:  0 - directory does not exist;  1 - directory does exist  */

Set directoryExists=##class(%File).DirectoryExists(directoryName)

If ('directoryExists)  // do the processing for when a directory does not exist

Outlined below is an example of how to check if a file exists:

How would you like to be able to access the Web Terminal directly from your VSCode?

InterSystems FAQ rubric

For routines (*.mac)

You can hide the source by exporting/importing only the *.obj that is generated after compiling the source program.

The command execution example specifies EX1Sample.obj and EX2Sample.obj, which are generated by compiling EX1Sample.mac and EX2Sample.mac, as export targets and exports them to the second argument file.

After moving to another namespace, I am using the exported XML file to perform the import.

After reading Stephen Wilson's article "Windows 7 performs shutdown too fast for Cache to close and so it gets forced down" I've recalled another solution that was based on Local Group Policy, which allows to control extra actions that should occur on computer startup or shutdown. How to add a computer shutdown script is well documented in MS Technet article.