I'm trying to build someone else's c++ project-- I'm using the code from here. It's a release of the project, so I believe it's supposed to work as is. However, on compiling I get this error. I've tried moving __gammaTable into the gamma() function, but am not really sure why this isn't considered in its scope.
src/gamma.cpp:15:9: error: 'prog_uchar' does not name a type
PROGMEM prog_uchar __gammaTable[] = {
^
In file included from /usr/share/arduino/hardware/arduino/cores/arduino/Arduino.h:8:0,
from src/gamma.h:4,
from src/gamma.cpp:13:
src/gamma.cpp: In function 'byte gamma(byte)':
src/gamma.cpp:42:27: error: '__gammaTable' was not declared in this scope
return pgm_read_byte(&__gammaTable[x*2 + 2]);
^
.build/lilypad328/Makefile:339: recipe for target '.build/lilypad328/src/gamma.o' failed
make: *** [.build/lilypad328/src/gamma.o] Error 1
Make failed with code 2
And here's code tripping the error:
#include "gamma.h"
PROGMEM prog_uchar __gammaTable[] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2,
2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4,
4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 7, 7,
7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 9, 10, 10, 10, 10, 11,
11, 11, 12, 12, 12, 13, 13, 13, 13, 14, 14, 14, 15, 15, 16, 16,
16, 17, 17, 17, 18, 18, 18, 19, 19, 20, 20, 21, 21, 21, 22, 22,
23, 23, 24, 24, 24, 25, 25, 26, 26, 27, 27, 28, 28, 29, 29, 30,
30, 31, 32, 32, 33, 33, 34, 34, 35, 35, 36, 37, 37, 38, 38, 39,
40, 40, 41, 41, 42, 43, 43, 44, 45, 45, 46, 47, 47, 48, 49, 50,
50, 51, 52, 52, 53, 54, 55, 55, 56, 57, 58, 58, 59, 60, 61, 62,
62, 63, 64, 65, 66, 67, 67, 68, 69, 70, 71, 72, 73, 74, 74, 75,
76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,
92, 93, 94, 95, 96, 97, 98, 99,100,101,102,104,105,106,107,108,
109,110,111,113,114,115,116,117,118,120,121,122,123,125,126,127
};
byte gamma(byte x) {
return pgm_read_byte(&__gammaTable[x*2 + 2]);
}
A quick fix is to change "prog_uchar" to "uchar". It looks like the table contains integers in the range (0,255), and "prog_uchar" is supposed to mean "uchar".
But the proper way to fix it is to find where "prog_uchar" is defined, and #include that file.
Your actual error is this:
src/gamma.cpp:15:9: error: 'prog_uchar' does not name a type
You are probably missing the header file where prog_uchar is included:
#include <avr/pgmspace.h>
This error:
src/gamma.cpp:42:27: error: '__gammaTable' was not declared in this scope
return pgm_read_byte(&__gammaTable[x*2 + 2]);
simply comes from the fact that, since prog_uchar is missing, the variable __gammaTable is not properly declared.
Related
I want to inline the function MyClass:at(), but performance isn't as I expect.
MyClass.cpp
#include <algorithm>
#include <chrono>
#include <iostream>
#include <vector>
#include <string>
// Making this a lot shorter than in my actual program
std::vector<std::vector<int>> arrarr =
{
{ 1, 70, 54, 71, 83, 51, 54, 69, 16, 92, 33, 48, 61, 43, 52, 1, 89, 19, 67, 48},
{24, 47, 32, 60, 99, 3, 45, 2, 44, 75, 33, 53, 78, 36, 84, 20, 35, 17, 12, 50},
{32, 98, 81, 28, 64, 23, 67, 10, 26, 38, 40, 67, 59, 54, 70, 66, 18, 38, 64, 70},
{67, 26, 20, 68, 2, 62, 12, 20, 95, 63, 94, 39, 63, 8, 40, 91, 66, 49, 94, 21},
{24, 55, 58, 5, 66, 73, 99, 26, 97, 17, 78, 78, 96, 83, 14, 88, 34, 89, 63, 72},
{21, 36, 23, 9, 75, 0, 76, 44, 20, 45, 35, 14, 0, 61, 33, 97, 34, 31, 33, 95},
{78, 17, 53, 28, 22, 75, 31, 67, 15, 94, 3, 80, 4, 62, 16, 14, 9, 53, 56, 92},
{16, 39, 5, 42, 96, 35, 31, 47, 55, 58, 88, 24, 0, 17, 54, 24, 36, 29, 85, 57},
{86, 56, 0, 48, 35, 71, 89, 7, 5, 44, 44, 37, 44, 60, 21, 58, 51, 54, 17, 58},
{19, 80, 81, 68, 5, 94, 47, 69, 28, 73, 92, 13, 86, 52, 17, 77, 4, 89, 55, 40},
{ 4, 52, 8, 83, 97, 35, 99, 16, 7, 97, 57, 32, 16, 26, 26, 79, 33, 27, 98, 66},
{88, 36, 68, 87, 57, 62, 20, 72, 3, 46, 33, 67, 46, 55, 12, 32, 63, 93, 53, 69},
{ 4, 42, 16, 73, 38, 25, 39, 11, 24, 94, 72, 18, 8, 46, 29, 32, 40, 62, 76, 36},
{20, 69, 36, 41, 72, 30, 23, 88, 34, 62, 99, 69, 82, 67, 59, 85, 74, 4, 36, 16},
{20, 73, 35, 29, 78, 31, 90, 1, 74, 31, 49, 71, 48, 86, 81, 16, 23, 57, 5, 54},
{ 1, 70, 54, 71, 83, 51, 54, 69, 16, 92, 33, 48, 61, 43, 52, 1, 89, 19, 67, 48},
};
class MyClass
{
public:
MyClass(std::vector<std::vector<int>> arr) : arr(arr)
{
rows = arr.size();
cols = arr.at(0).size();
}
inline auto at(int row, int col) const { return arr[row][col]; }
void arithmetic(int n) const;
private:
std::vector<std::vector<int>> arr;
int rows;
int cols;
};
MyClass.cpp:
void MyClass::arithmetic(int n) const
{
using std::chrono::high_resolution_clock;
using std::chrono::duration_cast;
using std::chrono::duration;
using std::chrono::milliseconds;
auto t1 = high_resolution_clock::now();
int highest_product = 0;
for (auto y = 0; y < rows; ++y)
{
for (auto x = 0; x < cols; ++x)
{
// Horizontal product
if (x + n < cols)
{
auto product = 1;
for (auto i = 0; i < n; ++i)
{
product *= at(y, x + i);
}
highest_product = std::max(highest_product, product);
}
}
}
auto t2 = high_resolution_clock::now();
duration<double, std::milli> ms_double = t2 - t1;
std::cout << ms_double.count() << "ms\n";
return highestProduct;
};
Now what I want know is why do I get better performance when I replace product *= at(y, x + i); with product *= arr[y][x+i];? When I test it with the first case, the timing on my large array takes roughly 6.7ms, and the second case takes 5.3ms. I thought when I inlined the function, it should be the same implementation as the second case.
Member function directly defined in the class definition (typically in header files) are implicitly inlined so using inline is useless in this case. inline do not guarantee the function is inlined. It is just an hint for the compiler. The keyword is also an important during the link to avoid the multiple-definition issue. Function that are not make inline can still be inlined if the compiler can see the code of the target function (ie. it is in the same translation unit or link time optimization are applied). For more information about this, please read Why are class member functions inlined?
Note that the inlining is typically performed in the optimization step of compilers (eg. -O1//O1). Thus without optimizations, most compilers will not inline the function.
Using std::vector<std::vector<int>> is not efficient since it is not a contiguous data structure and it require 2 indirection to access an item. Two sub-vectors next to each other can be stored far away in memory likely causing more cache misses (and/or thrashing due to the alignment). Please consider using one big flatten array and access items using y*cols+x where cols is the size of the sub-vectors (20 here). Alternatively a int[16][20] data type should do the job well if the size if fixed at compile-time.
MyClass(std::vector<std::vector<int>> arr) cause the input parameter to be copied (and so all the sub-vectors). Please consider using a const std::vector<std::vector<int>>& type.
While at is convenient for checking bounds at runtime, this feature can strongly decrease performance. Consider using the operator [] if you do not need that. You can use assertions combined with flatten arrays so to get a fast code in release and a safe code in debug (you can enable/disable them by defining the NDEBUG macro).
[[0, 11, 1, 27, 29, 5],
[0, 11, 1, 118, 52, 31, 89, 113],
[0, 11, 1, 118, 52, 51, 47],
[0, 11, 1, 118, 52, 89, 42, 43, 4, 109],
[0, 11, 46, 39, 33, 54]]
The desired output is :
[[0, 11],
[0, 11, 1],
[0, 11, 1, 118, 52]]
keeping the order
I wrote a program in MSVS 2015, but I need to run it in MSVS 2013.
I get the error
"Error 1 error C2661: 'std::vector>::vector' :
no overloaded function takes 21
arguments \vmwfil04\students$\1302273\visual studio
2013\projects\dartsc++2013\dartsc++2013\gui.h 22 1"
This problem is affecting all of my vectors I've created before runtime.
What could be causing this?
offending code:
vector<int> Double{ 0, 40, 2, 36, 8, 26, 12, 20, 30, 4, 34, 6, 38, 14, 32, 16, 22, 28, 18, 24, 10 };
vector<int> Normal{ 0, 20, 1, 18, 4, 13, 6, 10, 15, 2, 17, 3, 19, 7, 16, 8, 11, 14, 9, 12, 5 };
vector<int> Treble{ 0, 60, 3, 54, 12, 39, 18, 30, 45, 6, 39, 9, 57, 21, 48, 24, 33, 42, 27, 36, 15 };
vector<int> Bull { 0, 25, 50};
Support for these list-initialisers was new in VS 2015. It's not present in VS 2013. So you can't do it.
You'll have to take the old-fashioned, C++03 approach instead.
I believe this is a bug in Visual Studio 2013 as it does support list initializers (2013 specific documentation of the functionality). Try enclosing the brackets in a parenthesis per this answer.
e.g. vector<int> Double({ 0, 40, 2, 36, 8, 26, 12, 20, 30, 4, 34, 6, 38, 14, 32, 16, 22, 28, 18, 24, 10 });
I have a question which can be divided into two subquestions.
I have created a table the code of which is given below.
Problem 1.
xstep = 1;
xmaximum = 6;
numberofxnodes = 6;
numberofynodes = 3;
numberofzlayers = 3;
maximumgridnodes = numberofxnodes*numberofynodes
mnodes = numberofxnodes*numberofynodes*numberofzlayers;
orginaltable =
Table[{i,
node2 = i + xstep, node3 = node2 + xmaximum,
node4 = node3 - xstep,node5 = i + maximumgridnodes,
node6 = node5 + xstep,node7 = node6 + xmaximum,
node8 = node7 - xstep},
{i, 1, mnodes}]
If I run this I will get my original table. Basically I want to remove the sixth element and multiples of the sixth element from my original table. I am able to do this by using this code below.
modifiedtable = Drop[orginaltable, {6, mnodes, 6}]
Now I get the modified table where every sixth element and multiples of sixth element of my original table is removed. This solves my Problem 1.
Now my Problem 2:
** MAJOR EDITED VERSION**:(ALL THE CODES GIVEN ABOVE IS CORRECT)
Thanks a lot for the answers, but I wanted something else and I made a mistake
while explaining it initially so I'm making another try.
Below is my modified table: I want the elements in between
"/** and **/" deleted and remaining there.
{{1, 2, 8, 7, 19, 20, 26, 25}, {2, 3, 9, 8, 20, 21, 27, 26}, {3, 4,10, 9, 21, 22, 28, 27}, {4, 5, 11, 10, 22, 23, 29, 28}, {5, 6, 12, 11, 23, 24, 30, 29}, {7, 8, 14, 13, 25, 26, 32, 31}, {8, 9, 15, 14, 26, 27, 33, 32}, {9, 10, 16, 15, 27, 28, 34, 33}, {10, 11, 17, 16, 28, 29, 35, 34}, {11, 12, 18, 17, 29, 30, 36, 35}, /**{13, 14, 20, 19, 31, 32, 38, 37}, {14, 15, 21, 20, 32, 33, 39, 38}, {15, 16, 22, 21, 33, 34, 40, 39}, {16, 17, 23, 22, 34, 35, 41, 40}, {17, 18, 24, 23, 35, 36, 42, 41},**/ {19, 20, 26, 25, 37, 38, 44, 43}, {20, 21, 27, 26, 38, 39, 45, 44}, {21, 22, 28, 27, 39, 40, 46, 45}, {22, 23, 29, 28, 40, 41, 47, 46}, {23, 24, 30, 29, 41, 42, 48, 47}, {25, 26, 32, 31,43, 44, 50, 49}, {26, 27, 33, 32, 44, 45, 51, 50}, {27, 28, 34, 33, 45, 46, 52, 51}, {28, 29, 35, 34, 46, 47, 53, 52}, {29, 30, 36, 35, 47, 48, 54, 53}, /**{31, 32, 38, 37, 49, 50, 56, 55}, {32, 33, 39, 38,50, 51, 57, 56}, {33, 34, 40, 39, 51, 52, 58, 57}, {34, 35, 41, 40, 52, 53, 59, 58}, {35, 36, 42, 41, 53, 54, 60, 59},**/ {37, 38, 44, 43,55, 56, 62, 61}, {38, 39, 45, 44, 56, 57, 63, 62}, {39, 40, 46, 45, 57, 58, 64, 63}, {40, 41, 47, 46, 58, 59, 65, 64}, {41, 42, 48, 47,59, 60, 66, 65}, {43, 44, 50, 49, 61, 62, 68, 67}, {44, 45, 51, 50, 62, 63, 69, 68}, {45, 46, 52, 51, 63, 64, 70, 69}, {46, 47, 53, 52, 64, 65, 71, 70}, {47, 48, 54, 53, 65, 66, 72, 71}, /**{49, 50, 56, 55, 67, 68, 74, 73}, {50, 51, 57, 56, 68, 69, 75, 74},{51,52, 58, 57, 69, 70, 76, 75}, {52, 53, 59, 58, 70, 71, 77, 76}, {53, 54, 60, 59, 71, 72, 78, 77}}**/
Now, if you observe, I wanted the first ten elements
(1st to 10th element of modifiedtable) to be there in my final table
( DoubleModifiedTable ). the the next five (11th to 15th elements of modifiedtable) deleted.
Then the next ten elements ( 16th to 25th elements of modifiedtable)
to be present in my final table ( DoubleModifiedTable )
then the next five deleted (26th to 30th elements of modifiedtable) and so on for the whole table.
Let say we solve this problem and we name the final table DoubleModifiedTable.
I am basically interested in getting the DoubleModifiedTable. I decided to subdivide the problem as it easy to explain.
I want this to happen automatically through the table since as this is just an example table but in reality I have huge table. If I can understand how I can solve this problem for this table, then I can solve it for my large table too.
Perhaps simpler:
DoubleModifiedTable =
Module[{copy = modifiedtable},
copy[[Flatten[# + Range[5] & /# Range[10, Length[copy], 10]]]] = Sequence[];
copy]
EDIT
Even simpler:
DoubleModifiedTable =
Delete[modifiedtable,
Transpose[{Flatten[# + Range[5] & /# Range[10, Length[modifiedtable], 10]]}]]
EDIT 2
Per OP's request: one only has to change a single number (10 to 15) in any of my solutions to get the answer to a modified problem:
DoubleModifiedTable =
Delete[modifiedtable,
Transpose[{Flatten[# + Range[5] & /# Range[10, Length[modifiedtable], 15]]}]]
Another way is to do something like
DoubleModifiedTable = With[{n = 10, m = 5},
Flatten[{{modifiedtable[[;; m]]},
Partition[modifiedtable, n - m, n, {n - m + 1, 1}, {}]}, 2]]
Edit
The edited version of Problem 2 is actually slightly simpler to solve than the original version. You could for example do something like
DoubleModifiedTable =
With[{n = 10, m = 5}, Flatten[Partition[modifiedtable, n, n + m, 1, {}], 1]]
Edit 2
What my second version does is to split the original list modifiedtable into sublists using Partition and then to flatten these sublists to form the final list. If you look at the Documentation for Partition you can see that I'm using the 6th form of Partition which means that the length of the sublists is n and the offset (the distance be is n+m. The gap between the sublists is therefore n+m-n==m.
The next argument, 1, is actually equivalent to {1,1} which tells Mathematica that the first element of modifiedtable should appear at position 1 in the first sublist and the last element of modifiedtable should appear on or after position 1 of the last sublist.
The last argument, {} is to indicate that no padding should be used for sublists with length <=n.
In summary, if you want to delete the first 10 elements and keep the next 5 you want sublists of length n=5 with gap m=10. Since you want the first sublist to start with the (m+1)-th element of modifiedtable, you could replace the fourth argument in Partition with something of the form {k,1} for some value of k but it's probably easier to just drop the first m elements of modifiedtable beforehand, i.e.
DoubleModifiedTable =
With[{n = 5, m = 10},
Flatten[Partition[Drop[modifiedtable, m], n, n + m, 1, {}], 1]]
DoubleModifiedTable=
modifiedtable[[
Complement[
Range[Length[modifiedtable]],
Flatten#Table[10 i + j, {i, Floor[Length[modifiedtable]/10]}, {j, 5}]
]
]]
or, slightly shorter
DoubleModifiedTable=
#[[
Complement[
Range[Length[#]],
Flatten#Table[10 i + j, {i, Floor[Length[#]/10]}, {j, 5}]
]
]] & # modifiedtable
I have two questions,
Q1.
The code is below:
orgtable = Table[{i, node2 = i + 1, node3 = node2 + 6, node4 = node3 - 1,
node5 = i + 18, node6 = node5 + 1, node7 = node6 + 6,
node8 = node7 - 1}, {i, 1, 36}
];
modtable = Drop[orgtable, {6, 36, 6}];
finaltable = With[{n = 5, m = 10},Flatten[Partition[modtable, n, n + m, 1, {}], 1]]
The first piece of code gives me an original table, the second one gives me a modified table, and the third yields the final table.
The output of the final table looks like this:
{{1, 2, 8, 7, 19, 20, 26, 25}, {2, 3, 9, 8, 20, 21, 27, 26},
{3, 4, 10, 9, 21, 22, 28, 27}, {4, 5, 11, 10, 22, 23, 29, 28},
{5, 6, 12,11, 23, 24, 30, 29}, {19, 20, 26, 25, 37, 38, 44,43},
{20, 21, 27,26, 38, 39, 45, 44}, {21, 22, 28, 27, 39, 40, 46, 45},
{22, 23, 29,28, 40,41, 47, 46}, {23, 24, 30, 29, 41, 42, 48, 47}}
But I want it to set up a counter to the final table so that my output should look like this(below):The counter will increase by 1 and in the below example it will start with 200;
{{200,1, 2, 8, 7, 19, 20, 26, 25}, {201,2, 3, 9, 8, 20, 21, 27, 26},
{202,3, 4,10, 9, 21,22, 28, 27}, {203,4, 5, 11, 10, 22, 23, 29, 28},
{204,5, 6, 12,11, 23, 24, 30, 29} and so on
As you can see from the desired output the count is present for each element and increases by one
Now question number two:
mycounter = 100;
tryone =
TableForm[
Flatten[
Table[{++mycounter, xcord, ycord,
(150*(Sin[((xcord - 90*2*3.14)/180]^2)*
(Sin[((ycord - 45)*2*3.14)/180]^2)
) + 20
}, {xcord, 0, 200, 5}, {ycord, 0, 200, 5}
], 1
]
]
In the above example, I have successfully implemented a counter which is starting from 100 and incrementing by 1 and it gives me an output
100 0 0 20.03
101 0 5 20.04 and so on..
But now I want to use the Transpose function on this, since I want to transpose the value presented but at the same time I don't want to transpose the "my counter".
mycounter = 100;
secondtry=
TableForm[
Flatten[
Transpose[
Table[{++mycounter, xcord, ycord,
(150*(Sin[((xcord - 90)*2*3.14)/180]^2)*
(Sin[((ycord - 45)*2*3.14)/180]^2)
) +20}, {xcord, 0, 200, 5}, {ycord, 0, 200, 5}
]
], 1
]
]
But as you can see the Transpose function transposes also the "mycounter" which I do not want. How do you prevent the transpose function from working on "mycounter" but work on the rest of it?
Any other idea of implementing a counter in the above code is also welcome.
Removed answer to first question as I probably didn't understand what you wanted.
As to the second question: I'm not sure whether I fully understand you here. If the counter belongs to the coordinate set the output should be left as it is, how awkward it may look. If the counter column is simply a line counter of the final output you could put in after you have done your flattening just like before.
But in this case, it seems the Transpose is fully superfluous. It suffices to switch the order of the indices of your table. If you do that you can leave your counter as it is:
mycounter = 100;
secondtry =
Flatten[
Table[{mycounter++, xcord,ycord,
(150*(Sin[((xcord - 90)*2*3.14)/180]^2)*
(Sin[((ycord - 45)*2*3.14)/180]^2)
) + 20},
{ycord,0, 200, 5}, {xcord, 0, 200, 5} (* order switched here *)
], 1
]
A few notes: I removed the TableForm from your assignment. This is generally only used for printing and not for data that gets assigned to a variable. If you want to do an assignment and want to see the result at the same time you could try something like
(myVar = Table[...{...},{...}] ) //TableForm
Also note that you don't have to multiply by 3.14/180 to convert degrees to radians. Mathematica has a built-in quantity named Degree for that (if you use the shortcut esc deg esc you will have a nice degree symbol instead). It looks like you are multiplying with 2 pi/180 for this conversion. If that was your intention, it was incorrect. The conversion is either 2 pi/360 or pi/180. ((xcord - 90)*2*3.14)/180 should then be written as (xcord - 90)Degree.
Question 1 :
Transpose[Prepend[Transpose[#], Range[Length[#]] + 200]] &#
{{1, 2, 8, 7, 19, 20, 26, 25}, {2, 3, 9, 8, 20, 21, 27, 26}, {3, 4,
10, 9, 21, 22, 28, 27}, {4, 5, 11, 10, 22, 23, 29, 28}, {5, 6, 12,
11, 23, 24, 30, 29}, {19, 20, 26, 25, 37, 38, 44, 43}, {20, 21, 27,
26, 38, 39, 45, 44}, {21, 22, 28, 27, 39, 40, 46, 45}, {22, 23,
29, 28, 40, 41, 47, 46}, {23, 24, 30, 29, 41, 42, 48, 47}}
Question2:
Function[mat,
Partition[
Transpose[Prepend[Transpose[#], Range[Length[#]] + 99]] &#
Flatten[mat, 1], Length[mat]]]#
Table[{xcord,
ycord, (150*(Sin[((xcord - 90)*2*3.14)/
180]^2)*(Sin[((ycord - 45)*2*3.14)/180]^2)
) + 20
}, {xcord, 0, 200, 50}, {ycord, 0, 200, 50}
]
Create the rest of the table without the counter, create a suitable n*1 matrix of the index using Range, and then use MapThread with the inner function Join to put the two together.
Your finaltable could also be produced from modtable using Table as follows:
finaltableAlt = Delete[#, Transpose#{Flatten#Table[i + j, {i, 5, (
Length[#] - 10), 15}, {j, 10}]}] & # modtable
Another possibility for numbering:
MapIndexed[Flatten#{#2[[1]] + 199, #1} &, finaltableAlt]