The Ring programming language version 1.5.2 book - Part 34 of 181

1. Ring Documentation, Release 1.5.2
Syntax:
Endswith(string, substring) ---> True/False
Example:
Load "stdlib.ring"
Puts("Test Endswith()")
see endsWith("CalmoSoft", "Soft") + nl
42.28 gcd() function
Finding of the greatest common divisor of two integers.
Syntax:
Gcd(number,number) ---> number
Example:
Load "stdlib.ring"
Puts("Test Gcd()")
see gcd (24, 32) + nl
42.29 lcm() function
Compute the least common multiple of two integers.
Syntax:
lcm(number,number) ---> number
Example:
Load "stdlib.ring"
Puts("Test Lcm()")
see Lcm(24,36) + nl
42.30 sumlist() function
Compute the sum of a list of integers.
Syntax:
sumlist(list) ---> number
Example:
Load "stdlib.ring"
Puts("Test Sumlist()")
42.28. gcd() function 305

2. Ring Documentation, Release 1.5.2
aList = [1,2,3,4,5]
see Sumlist(aList) + nl
42.31 prodlist() function
Compute the product of a list of integers.
Syntax:
prodlist(list) ---> number
Example:
Load "stdlib.ring"
Puts("Test Prodlist()")
aList = [1,2,3,4,5]
see Prodlist(aList) + nl
42.32 evenorodd() function
Test whether an integer is even or odd.
Result of test (1=odd 2=even).
Syntax:
evenorodd(number) ---> 1 (odd) or 2 (even)
Example:
Load "stdlib.ring"
Puts("Test Evenorodd()")
nr = 17
see Evenorodd(nr) + nl
42.33 factors() function
Compute the factors of a positive integer.
Syntax:
factors(list) ---> list
Example:
Load "stdlib.ring"
Puts("Test Factors()")
n = 45
aList = factors(n)
see "Factors of " + n + " = "
for i = 1 to len(aList)
42.31. prodlist() function 306

3. Ring Documentation, Release 1.5.2
see "" + aList[i] + " "
next
42.34 palindrome() function
Check if a sequence of characters is a palindrome or not.
Syntax:
Palindrome(String) ---> True/False
Example:
Load "stdlib.ring"
Puts("Test Palindrome()")
cString = "radar"
see Palindrome(cString)
42.35 isleapyear() function
Check whether a given year is a leap year in the Gregorian calendar.
Syntax:
Isleapyear(number) ---> True/False
Example:
Load "stdlib.ring"
Puts("Test Isleapyear()")
year = 2016
if Isleapyear(year) see "" + year + " is a leap year."
else see "" + year + " is not a leap year." ok
42.36 binarydigits() function
Compute the sequence of binary digits for a given non-negative integer.
Syntax:
binarydigits(number) ---> string
Example:
Load "stdlib.ring"
Puts("Test Binarydigits()")
b = 35
see "Binary digits of " + b + " = " + Binarydigits(b)
42.34. palindrome() function 307

4. Ring Documentation, Release 1.5.2
42.37 matrixmulti() function
Multiply two matrices together.
Syntax:
Matrixmulti(List,List) ---> List
Example:
Load "stdlib.ring"
# Multiply two matrices together.
Puts("Test Matrixmulti()")
A = [[1,2,3], [4,5,6], [7,8,9]]
B = [[1,0,0], [0,1,0], [0,0,1]]
see Matrixmulti(A, B)
42.38 matrixtrans() function
Transpose an arbitrarily sized rectangular Matrix.
Syntax:
Matrixtrans(List) ---> List
Example:
Load "stdlib.ring"
# Transpose an arbitrarily sized rectangular Matrix.
Puts("Test Matrixtrans()")
matrix = [[78,19,30,12,36], [49,10,65,42,50], [30,93,24,78,10], [39,68,27,64,29]]
see Matrixtrans(matrix)
42.39 dayofweek() function
Return the day of the week of given date. (yyyy-mm-dd)
Syntax:
dayofweek(string) ---> string
Example:
Load "stdlib.ring"
# Return the day of the week of given date.
Puts("Test Dayofweek()")
date = "2016-04-24"
see "Data : " + date + " - Day : " + Dayofweek(date) + nl
42.37. matrixmulti() function 308

5. Ring Documentation, Release 1.5.2
42.40 permutation() function
Generates all permutations of n different numerals.
Syntax:
permutation(list)
Example:
Load "stdlib.ring"
# Generates all permutations of n different numerals
Puts("Test Permutation()")
list = [1, 2, 3, 4]
for perm = 1 to 24
for i = 1 to len(list)
see list[i] + " "
next
see nl
Permutation(list)
next
42.41 readline() function
Read line from file
Syntax:
readline(fp) ---> string
Example:
Load "stdlib.ring"
# Read a file line by line.
Puts("Test Readline()")
fp = fopen("test.ring","r")
while not feof(fp)
See Readline(fp) end
fclose(fp)
42.42 substring() function
Return a position of a substring starting from a given position in a string.
Syntax:
Substring(str,substr,npos) ---> string
Example:
Load "stdlib.ring"
# Return a position of a substring starting from a given position in a string.
42.40. permutation() function 309

6. Ring Documentation, Release 1.5.2
Puts("Test Substring()")
a = "abcxyzqweabc"
b = "abc"
i = 4
see substring(a,b,i)
42.43 changestring() function
Change substring from given position to a given position with another substring.
Syntax:
Changestring(cString, nPos1, nPos2, cSubstr) ---> cString
Example:
Load "stdlib.ring"
# Change substring from given position for given position with a substring.
Puts("Test Changestring()")
see Changestring("Rmasdg",2,5,"in") # Ring
42.44 sleep() function
Sleep for the given amount of time.
Syntax:
sleep(nSeconds)
Example:
Load "stdlib.ring"
Puts("Test Sleep()")
see "Wait 3 Seconds!"
Sleep(3)
see nl
42.45 ismainsourcefile() function
Check if the current file is the main source file
Syntax:
IsMainSourceFile() ---> True/False
Example:
Load "stdlib.ring"
if ismainsourcefile()
# code
ok
42.43. changestring() function 310

7. Ring Documentation, Release 1.5.2
42.46 direxists() function
Check if directory exists
Syntax:
DirExists(String) ---> True/False
Example:
Load "stdlib.ring"
see "Check dir : b:ring "
puts( DirExists("b:ring") )
see "Check dir : C:ring "
Puts( DirExists("C:ring") )
42.47 makedir() function
Make Directory
Syntax:
MakeDir(String)
Example:
Load "stdlib.ring"
# Create Directory
puts("create Directory : myfolder")
makedir("myfolder")
42.48 fsize() function
The function return the file size in bytes.
Syntax:
FSize(File Handle) ---> Number (File Size in Bytes)
42.49 trimall() function
Remove all spaces and tabs characters from a string
Syntax:
TrimAll(cString) ---> cString # Without Spaces and Tabs
42.46. direxists() function 311

8. Ring Documentation, Release 1.5.2
42.50 trimleft() function
Remove all spaces and tabs characters from the left side of a string
Syntax:
TrimLeft(cString) ---> cString # Without Spaces and Tabs from the left side
42.51 trimright() function
Remove all spaces and tabs characters from the right side of a string
Syntax:
TrimRight(cString) ---> cString # Without Spaces and Tabs from the right side
42.52 epochtime() function
Return the Epoch Time
Syntax:
EpochTime(cDate,cTime) ---> nEpochTime
Example:
see EpochTime( Date(), Time() )
42.53 SystemCmd() Function
We can execute system commands using the SystemCmd() function that outputs to a variable
Syntax:
SystemCmd(cCommand)
Example:
cYou = SystemCmd("whoami") # User Name logged in is output a variable
cThem = SystemCmd("dir c:Users") # Directory List is output to a variable
42.54 ListAllFiles() Function
Using this function we can quickly do a process on a group of files in a folder and it’s sub folders.
Syntax:
ListAllFiles(cFolder,cExtension) ---> List of Files
Example:
42.50. trimleft() function 312

9. Ring Documentation, Release 1.5.2
aList = ListAllFiles("c:/ring/ringlibs","ring") # *.ring only
aList = sort(aList)
see aList
Example:
see listallfiles("b:/ring/ringlibs/weblib","") # All Files
42.54. ListAllFiles() Function 313

10. CHAPTER
FORTYTHREE
STDLIB CLASSES
In this chapter we are going to learn about the classes in the stdlib.ring
• StdBase Class
• String Class
• List Class
• Stack Class
• Queue Class
• HashTable Class
• Tree Class
• Math Class
• DateTime Class
• File Class
• System Class
• Debug Class
• DataType Class
• Conversion Class
• ODBC CLass
• MySQL Class
• SQLite Class
• Security Class
• Internet Class
43.1 StdBase Class
Attributes:
• vValue : Object Value
Methods:
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