public int maandLengte(Maand maand, int jaar) { switch(maand) { case FEB: GregorianCalendar g = new GregorianCalendar(); if (g.isLeapYear(jaar)) { return 29; } else { return 28; } case APR: case JUN: case SEP: case NOV: return 30; default: return 31; } }
Tag Archives: programming
date crap
How to get the current epoch time in …
| Perl | time |
| PHP | time() |
| Ruby | Time.now (or Time.new). To display the epoch: Time.now.to_i |
| Python | import time first, then time.time() |
| Java | long epoch = System.currentTimeMillis()/1000; |
| Microsoft .NET C# | epoch = (DateTime.Now.ToUniversalTime().Ticks - 621355968000000000) / 10000000; |
| VBScript/ASP | DateDiff("s", "01/01/1970 00:00:00", Now()) |
| Erlang | calendar:datetime_to_gregorian_seconds(calendar:now_to_universal_time( now()))-719528*24*3600. |
| MySQL | SELECT unix_timestamp(now())  |
| PostgreSQL | SELECT extract(epoch FROM now()); |
| Oracle PL/SQL | SELECT (SYSDATE - TO_DATE('01-01-1970 00:00:00', 'DD-MM-YYYY HH24:MI:SS')) * |
| SQL Server | SELECT DATEDIFF(s, '1970-01-01 00:00:00', GETUTCDATE()) |
| JavaScript | Math.round(new Date().getTime()/1000.0) getTime() returns time in milliseconds. |
| Unix/Linux | date +%s |
| PowerShell | Get-Date -UFormat "%s" Produces: 1279152364.63599 |
| Other OS’s | Command line: perl -e "print time" (If Perl is installed on your system) |
Convert from human readable date to epoch
| Perl | Use these Perl Epoch routines |
| PHP | mktime(hour, minute, second, month, day, year) |
| Ruby | Time.local(year, month, day, hour, minute, second, usec ) (or Time.gm for GMT/UTC input). To display add .to_i |
| Python | import time first, then int(time.mktime(time.strptime('2000-01-01 12:34:00', '%Y-%m-%d %H:%M:%S'))) - time.timezone |
| Java | long epoch = new java.text.SimpleDateFormat ("dd/MM/yyyy HH:mm:ss").parse("01/01/1970 01:00:00"); |
| VBScript/ASP | DateDiff("s", "01/01/1970 00:00:00", time field) |
| MySQL | SELECT unix_timestamp(time) Time format: YYYY-MM-DD HH:MM:SS or YYMMDD or YYYYMMDDMore on using Epoch timestamps with MySQL |
| PostgreSQL | SELECT extract(epoch FROM date('2000-01-01 12:34'));With timestamp: SELECT EXTRACT(EPOCH FROM TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40-08');With interval: SELECT EXTRACT(EPOCH FROM INTERVAL '5 days 3 hours'); |
| SQL Server | SELECT DATEDIFF(s, '1970-01-01 00:00:00', time field) |
| JavaScript | use the JavaScript Date object |
| Unix/Linux | date +%s -d"Jan 1, 1980 00:00:01" Replace ‘-d’ with ‘-ud’ to input in GMT/UTC time. |
Convert from epoch to human readable date
| Perl | Use these Perl Epoch routines |
| PHP | date(output format, epoch); Output format example: ‘r’ = RFC 2822 date |
| Ruby | Time.at(epoch) |
| Python | import time first, then time.strftime("%a, %d %b %Y %H:%M:%S +0000", time.localtime(epoch)) Replace time.localtime with time.gmtime for GMT time. |
| Java | String date = new java.text.SimpleDateFormat("dd/MM/yyyy HH:mm:ss").format(new java.util.Date (epoch*1000)); |
| VBScript/ASP | DateAdd("s", epoch, "01/01/1970 00:00:00") |
| MySQL | from_unixtime(epoch, optional output format) The default output format is YYY-MM-DD HH:MM:SS more … |
| PostgreSQL | PostgreSQL version 8.1 and higher: SELECT to_timestamp(epoch); Older versions: SELECT TIMESTAMP WITH TIME ZONE 'epoch' + epoch * INTERVAL '1 second'; |
| SQL Server | DATEADD(s, epoch, '1970-01-01 00:00:00') |
| Microsoft Excel | =(A1 / 86400) + 25569 Format the result cell for date/time, the result will be in GMT time (A1 is the cell with the epoch number). For other timezones: =((A1 +/- timezone adjustment) / 86400) + 25569. |
| Crystal Reports | DateAdd("s", {EpochTimeStampField}-14400, #1/1/1970 00:00:00#) -14400 used for Eastern Standard Time. See Timezones. |
| JavaScript | use the JavaScript Date object |
| Unix/Linux | date -d @1190000000 Replace 1190000000 with your epoch, needs recent version of ‘date’. Replace ‘-d’ with ‘-ud’ for GMT/UTC time. |
| PowerShell | Function get-epochDate ($epochDate) { [timezone]::CurrentTimeZone.ToLocalTime(([datetime]'1/1/1970').AddSeconds($epochDate)) }, then use: get-epochDate 1279152364. Works for Windows PowerShell v1 and v2 |
| Other OS’s | Command line: perl -e "print scalar(localtime(epoch))" (If Perl is installed) Replace ‘localtime’ with ‘gmtime’ for GMT/UTC time. |
eclipse code completion
Change
Preferences > Keys > “content assist”
to something that doesn’t collide with Quicksilver.
create graphviz image from textfile
inspired by text2mindmap.com i decided to create something similar in python.
Here’s the result:
Code text2mindmap.py
#!/usr/bin/python import pydot import sys def ReadFile(filename): fh = open(filename) return [x.rstrip() for x in fh.readlines()] def CreateEdges(lines): edge_list= ['' for x in range(100)] edges = [] for line in lines: pos = line.count('\t'); edge_list[pos] = line.replace('\t', '') if pos: edges.append((edge_list[pos -1], edge_list[pos])) return edges def CreateGraphFromEdges(edges, output): g=pydot.graph_from_edges(edges, directed=True) return g.write_png('%s.png' % output, prog='dot') def main(argv): CreateGraphFromEdges(CreateEdges(ReadFile(argv[1])), argv[2]) if __name__ == "__main__": main(sys.argv)
Source file months.txt
Months of the year Spring March April May Summer June July August Autumn September October November Winter December January February
How to generate the image:
$ ./text2mindmap.py months.txt monthsprogramming fonts
proggyfonts has some awesome fonts listed, which work perfectly on smaller screens.
pydot + graphviz
Install pydot
Install graphviz
$ python Python 2.5.1 (r251:54863, Feb 9 2009, 18:49:36) [GCC 4.0.1 (Apple Inc. build 5465)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>> import pydot >>> edges=[('1','2'), ('1','3'), ('1','4'), ('3','4')] >>> g=pydot.graph_from_edges(edges) >>> g.write_jpeg('graph_from_edges_dot.jpg', prog='dot') True >>>
result:
C enums
#include <stdio .h> enum months { JAN = 1, FEB, MAR, APR, MAY, JUN, JUL, AUG, SEP, OCT, NOV, DEC }; const char *monthName[] = { "", "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December" }; int main() { enum months month; for (month = JAN; month < = DEC; month++) { puts(monthName[month]); } return 0; }
C pointers
* Once a variable is declared, we can get its address by preceding its name with the unary & operator, as in &k.
* We can “dereference” a pointer, i.e. refer to the value of that which it points to, by using the unary ‘*’ operator as in *ptr.
* An “lvalue” of a variable is the value of its address, i.e. where it is stored in memory.
The “rvalue” of a variable is the value stored in that variable (at that address).
#include <stdio .h> int main() { int k=3; int *ptr; ptr = &k; printf("The value ptr is pointing to:%d at address:%p\n", *ptr, ptr); } </stdio>
C prinft formatting
Where specifier is the most significant one and defines the type and the interpretation of the value of the coresponding argument:
| specifier | Output | Example |
|---|---|---|
| c | Character | a |
| d or i | Signed decimal integer | 392 |
| e | Scientific notation (mantise/exponent) using e character | 3.9265e+2 |
| E | Scientific notation (mantise/exponent) using E character | 3.9265E+2 |
| f | Decimal floating point | 392.65 |
| g | Use the shorter of %e or %f | 392.65 |
| G | Use the shorter of %E or %f | 392.65 |
| o | Signed octal | 610 |
| s | String of characters | sample |
| u | Unsigned decimal integer | 7235 |
| x | Unsigned hexadecimal integer | 7fa |
| X | Unsigned hexadecimal integer (capital letters) | 7FA |
| p | Pointer address | B800:0000 |
| n | Nothing printed. The argument must be a pointer to a signed int, where the number of characters written so far is stored. | |
| % | A % followed by another % character will write % to stdout. |
Strings in C
C doesn’t know about strings. It knows about characters, and thus, a string is an array of characters like so:
char the_string[] = "this is my fancy string";
Another way to allocate a number of chars is this:
char the_string[50];
To show that its really an array:
#include <stdio .h> int main() { char some_array[] = {'a', 'b', 'c'}; printf("%s\n", some_array); return 0; } </stdio>
Which yields:
abc
Here we create an array of characters named the_string. A string in C is terminated by the “\0″ (NULL) character.
Example of passing a string to a method called print:
#include <stdio .h> void print(char string[]) { printf("%s\n", string); } int main() { print("test 1 2 3"); return 0; } </stdio>