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Rails DB Migration - How To Drop a Table?
... information about how to accomplish different tasks in a migration here:
http://api.rubyonrails.org/classes/ActiveRecord/Migration.html
More specifically, you can see how to drop a table using the following approach:
drop_table :table_name
...
Convert tuple to list and back
...
List to Tuple and back can be done as below
import ast, sys
input_str = sys.stdin.read()
input_tuple = ast.literal_eval(input_str)
l = list(input_tuple)
l.append('Python')
#print(l)
tuple_2 = tuple(l)
# Make sure to name the final tuple 'tuple_2'
print(tuple_2)
...
How to know what the 'errno' means?
... answered Feb 2 '09 at 17:23
Commodore JaegerCommodore Jaeger
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...
What is the difference between 'typedef' and 'using' in C++11?
...uced by an
alias-declaration.
The identifier following the using keyword becomes a
typedef-name and the optional attribute-specifier-seq following the identifier appertains to that typedef-name. Such a
typedef-name has the same semantics as if it were introduced by the typedef specifier. [...]
a ty...
Setting WPF image source in code
...packUri = "pack://application:,,,/AssemblyName;component/Images/icon.png";
_image.Source = new ImageSourceConverter().ConvertFromString(packUri) as ImageSource;
share
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improve this answer
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How to convert a unix timestamp (seconds since epoch) to Ruby DateTime?
...cessary instead of DateTime. So use Time.strptime("1318996912345",'%Q').to_f and you will see the milliseconds preserved, while DateTime.strptime("1318996912345",'%Q').to_f does not preserve it.
– skensell
Feb 22 '17 at 15:20
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How does Dijkstra's Algorithm and A-Star compare?
...stance(int dist[], bool sptSet[])
{
// Initialize min value
int min = INT_MAX, min_index;
for (int v = 0; v < V; v++)
if (sptSet[v] == false && dist[v] <= min)
min = dist[v], min_index = v;
return min_index;
}
int printSolution(int dist[], int n)
{
printf("Vertex ...
get list from pandas dataframe column
...hon list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], index=['a', 'b', 'c', 'd'])}
df = pd.DataFrame(data_dict)
print(f"DataFrame:\n{df}\n")
print(f"column types:\n{df.dtyp...
How to extract an assembly from the GAC?
...
The method described here is very easy:
http://andreasglaser.net/post/2008/08/05/Extract-assembly-from-Global-Assembly-Cache-(GAC)-with-network-drive-mapping.aspx
Summary from Article:
Map a Network Drive (Explorer -> Tools)
Map to \servername\folder (\\You...
How to prevent vim from creating (and leaving) temporary files?
...
I added this to my _vimrc file on Windows, and I'm still getting file~ files. Am I not doing something correctly?
– FilBot3
Aug 26 '15 at 14:48
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