Tag: a

How do I get keys that correspond to values in Python dictionary?

Post author By Full Stack
Post date January 20, 2021
No Comments on How do I get keys that correspond to values in Python dictionary?

So let’s say I have a dictionary: my_dict = {‘A’ : 250, ‘B’ : 270, ‘C’ : 240} And I have a list that has values sorted in descending order: my_list = [270, 250, 240] Now, I want to create a list that looks like this: new_list = [‘B’, ‘A’, ‘C’] The elements are ordered […]

Tags 'B' : 270, 'C' : 240} And I have a list that has values sorted in descending order: my_list = [270, 'C'] The elements are ordered in accordance with my_list. How do I make this possible? Thanks., 240] Now, 250, a, I want to create a list that looks like this: new_list = ['B', So let's say I have a dictionary: my_dict = {'A' : 250

Mastering Development

How to use implicit conversion instead of structural typing when only one collection method is needed

Post author By Full Stack
Post date January 19, 2021
No Comments on How to use implicit conversion instead of structural typing when only one collection method is needed

I have a method in which I only need to access one method (appended, or :+) of a type. I want to be able to use both a custom case class and a normal List. Coming from a TypeScript background, I know how to do this using structural typing: case class CustomContainer[T](data: List[T]) { def […]

Tags 2, 3, 4) // CustomContainer(List(1, 4) // List(1, 4) append(CustomContainer(List(1, a, I have a method in which I only need to access one method (appended, I know how to do this using structural typing: case class CustomContainer[T](data: List[T]) { def :+(other: T): CustomContainer[T] = copy(, or :+) of a type. I want to be able to use both a custom case class and a normal List. Coming from a TypeScript background, other: T): A = appendable :+ other append(List(1

Mastering Development

How can i make this simple program work in C?

Post author By Full Stack
Post date January 19, 2021
No Comments on How can i make this simple program work in C?

I want to print out all numbers between 100,000 and 100 with the same digits reversed as fraction. eg. 100.001 101.101 102.201 103.301 104.401 … … 243.342 … 12345.54321 I dont know how to do this, so first I tried to make a simpler program to print out with the same fraction: eg. 100.100 12345.12345 […]

Tags 000 and 100 with the same digits reversed as fraction. eg. 100.001 101.101 102.201 103.301 104.401 ... ... 243.342 ... 12345.54321 I do, a, B, c--, d; for (number=100000; number>99; number--){ // printf("%f ", I want to print out all numbers between 100, number); if (number==100000){ a = number/100000000000; printf("%f ", number+a); } else if (number 9999){ b = number/100000; printf("%f ", number+b); } else if (number > 999 && number < 10000) { c= number / 10000; printf("%f ", number+c); } else if (number > 99 && number <1000) { d= number/ 1000; printf("%f ", number+d); } } return 0; } I have no idea how to reverse the fraction digits, so first I tried to make a simpler program to print out with the same fraction: eg. 100.100 12345.12345 243.243 #include #inclu, so i would be grateful if you could help me.

Database Development

Relation in BCNF or not

Consider the relation R[A,B,C,D,E] with: the keys {A,E}, {A,B,C} and {A,B,D} the functional dependency {A,C} -> {D} no repeating attributes What is the normal form of R? My answer: It is in 1NF because the are no repeating attributes, it’s also in 2NF because there is no partial dependency since {A,C} and {D} are keys, […]

Tags 3NF because there is no transitive dependency, a, B, but A, but also {A, but I don't know what to say about BCNF. BCNF is not satisfied when non-primary -> primary, c--, C} -> {D} no repeating attributes What is the normal form of R? My answer: It is in 1NF because the are no repeating attributes, C} and {A, C} and {D} are keys, C} and {D} are primary attributes, C} is just a subset of the key. Can somebody, Consider the relation R(A, d, D} the functional dependency {A, e, E] with: the keys {A, Help me please, it's also in 2NF because there is no partial dependency since {A

Mastering Development

Why is there an inconstancy between these two ways of plotting a function in Octave?

Post author By Full Stack
Post date January 19, 2021
No Comments on Why is there an inconstancy between these two ways of plotting a function in Octave?

Context I have a function named ibm that I defined with a simple if condition: it should be 0 until a certain value (500), then is linear after that value: function f = ibm(x) if(nargin != 1) usage("ibm(x)"); endif if(x <= 500) f = 0; else f = (x-500) *0.02; endif endfunction Then in a […]

Tags "ob"); xlabel("x"); ylabel("ibm(x)"); title("ibm(x) in for loop"); legend("ibm(x)"); Question Why the 1st (and most straightforward) method, "xr"); xlabel("x"); ylabel("ibm(x)"); title("ibm(x) directly computed"); legend("ibm(x)"); # for figure 2, a, and ended up with the same result (red wrong curve), and I checked some values below 500: if I type ibm(34) the result is 0 as expected, and I still don't know why. Figures Wrong Right, and then the result became what I expected (see figure 2, but not in the graph. Why this discrepancy? So after a while puzzling over this issue, Context I have a function named ibm that I defined with a simple if condition: it should be 0 until a certain value (500), directly computed (wrong plot result, I even tried the 1st way of plotting with Scilab, I tried adding the result values "manually" in a for loop, I wanted to plot this function with x in range from 0 to 1000, ibm(i)]; end figure(2); plot(x, ibm(x), ibm(x)); But the result did not show what I wanted: it showed a linear function without a flat part (see figure 1, in blue) a = []; for(i=x) a = [a, in for loop (correct plot result, in red) x=0:1:1000; figure(1); plot( x, so I tried to plot it with a simple x=0:1:1000; plot(x, so useless statement here # The function we want to plot function f = ibm(x) if(nargin != 1) usage("ibm(x)"); endif if(x <= 500), the blue graph). A complete code sample (MVE) here: This produces both figures (wrong and right) with the same function ibm. 1; # start of, the red graph). It did NOT correspond to the function results, then is linear after that value: function f = ibm(x) if(nargin != 1) usage("ibm(x)"); endif if(x <= 500) f = 0; else f =

Mastering Development System & Network

Enabling MySQL authentication for proftpd

Post author By Server Questions
Post date January 19, 2021
No Comments on Enabling MySQL authentication for proftpd

I am trying to use MySQL authentication for proftpd. I have configured everything and the authentication is working fine. The issue I am facing is that there is another database already being used for logs. So during the authentication time, the database user for the authentication is trying to write data to log database. proftpd[234014] […]

Mastering Development

How to store a generated, static set of bitsets in a minimized byte array

Post author By Full Stack
Post date January 18, 2021
No Comments on How to store a generated, static set of bitsets in a minimized byte array

Optimization problem: I have an array of bitsets, A, all containing integers in the range [0; 2047], all with at least 2 elements, all sets unique. I want to store them in a byte array, BA, where each bitset, S, is stored in a compressed format, BS starting with 2 bytes: b0, which indicates the […]

Tags -7.15, "Used", }; } // not used, $$10^-3$$, 0x00, 0x01, 0x01 // 7 elements, 0x02 // 3 elements, 0x0a // 2 elements, 0x0c // 2 elements, 0x28 // 2 elements, 0x70 // 3 elements, 0x71 // 4 elements, 0x88, 0xca // 4 elements, 0xd3 // 5 elements, 0xd7, 0xe0 // 3 elements, 10, 10] ; set 6 [5, 10] ; set 7 [8, 10] [1, 11] -> [10-11] /* [ 9] addr: 29 [ 12- 14] */, 11] ; set 8 [1, 12 13, 12-15] -> [0-1, 12-15] -> [0-2, 12-15] ; set 0 [7, 12-15] ; set 1 [5, 14-15] -> [1, 14-15] -> [5-7] /* [ 6] addr: 20 [ 1- 3] */, 14-15] ; set 3 [3, 14-15] ; set 5 [7, 14] ; set 4 [5, 14] [3, 15.0), 15] ; set 2 [7, 2, 3, 3 bytes, 3-5] [ 6], 3-5] [ 8], 3] /* [ 7] addr: 23 [ 3- 5] */, 4, 4 bytes, 4-6] /* [ 3] addr: 10 [ 1- 7] */, 5, 5.7, 5] /* [ 8] addr: 26 [ 10- 11] */, 6 10, 6-7] [ 11], 6-7] [ 4], 6-7] /* [ 2] addr: 7 [ 0- 6] */, 6-7] /* [ 4] addr: 13 [ 3- 9] */, 6-8] /* [ 1] addr: 4 [ 0- 7] */, 6)-> (2, 7, 7] [6, 9] -> [12-14] }; // Total size in bytes:32 Elements ordered by new value [ 0], 9] ; set 9 Output: static const unsigned char bitsetArray[] = { /* [ 0] addr: 0 [ 0- 8] */ 0x00, 9] /* [ 5] addr: 17 [ 5- 7] */, a, all containing integers in the range [0; 2047], all sets unique. I want to store them in a byte array, all with at least 2 elements, and the lookup function look like this: ByteArray dynamicBitSetToByteArray(const BitSet &bitSet) { if(bitSet.isEmpty()) throw EmptySetExce, and they can subsequently be found by simple indexing. Problem: Find the permutation of the integers represented in the bitsets in A, are concatenated in BA, are placed next to last The remaining bitsets form a connected graph... But then I'm stuck. Maybe some kind of steepest descent algorithm, as the bitsets must be available without prior decompression. The only purpose with the compressed bitsets is to determine if an integer is c, B|A, b0, b1); } ByteArray bytes(b1+1); bytes.addZeroes(b1+1); const UINT base = b0 << 3; for(auto it = bitSet.getIterator(); it.hasNext();), b1=%u. Must be < 256", bs, BS contains a maximum of 8 * 256 = 2048 bits. Thus BS is a set of integers in the interval [N0; N0+capacity-1], BS starting with 2 bytes: b0, contained in 0 sets:[] [ 1], contained in 0 sets:[] Elements ordered by old value [ 8], contained in 1 sets:[0] [ 12], contained in 1 sets:[0] [ 3], contained in 1 sets:[0] [ 9], contained in 1 sets:[4] [ 10], contained in 1 sets:[4] [ 13], contained in 1 sets:[8] [ 0], contained in 1 sets:[8] [ 11], contained in 1 sets:[8] [ 12], contained in 1 sets:[8] [ 14], contained in 1 sets:[9] [ 13], contained in 1 sets:[9] [ 14], contained in 1 sets:[9] [ 15], contained in 1 sets:[9] [ 2], contained in 1 sets:[9] [ 3], contained in 1 sets:[9] [ 5], contained in 3 sets:[0-2] [ 1], contained in 3 sets:[0-2] [ 4], contained in 3 sets:[0-2] [ 5], contained in 3 sets:[0-2] [ 7], contained in 3 sets:[2, contained in 4 sets:[0-1, contained in 4 sets:[3-4, contained in 5 sets:[0-1, contained in 5 sets:[0-3, containing the bits from S. That is, has a 1-bit at position indexed by v. bool dynamicBitsetContains(const BYTE *bitset, High, high = bitSet.getMax(); const UINT b0 = low >> 3; const UINT b1 = (high >> 3) - b0; if((b0 > 255) || (b1 > 255)) { throw Excep, ie., if this is a well known problem with or without any known efficient solution, if v is present in bitset, is stored in a compressed format, iterating until no decrease in the total size of BA. I don't know, Low, max] = [left, old Set:[0, old Set:[1, old Set:[3, old Set:[5, old Set:[7, old Set:[8, old value: 0, old value: 1, old value: 10, old value: 11, old value: 12, old value: 13, old value: 14, old value: 15, old value: 2, old value: 3, old value: 4, old value: 5, old value: 6, old value: 7, old value: 8, old value: 9, Optimization problem: I have an array of bitsets, or it is known to be an intractable problem. The function to generate BS from one bitset, right) + 2; } Sample data 16 ; Value range:[0..15] [0, right] UINT sizeofDynamicBitSet(UINT left, s, selecting the best swap of the remaining elements, so that the size of BA is minimized. I don't want to use zlib or any other general purpose compression algorithms, the condition (v<cap) will fail. const UINT cap = (((UINT)*(bitset++))+1) << 3; // Calculate capacity=8*(b1+1) = total number of bits ret, UINT right) { return (right>>3) - (left>>3) + 1; } // Return size in bytes of dynamic bitset with [min, UINT right) { return getBitSetByteCount(left, UINT v) { v -= ((UINT)*(bitset++)) << 3; // Subtract base=b0*8. If v is less, waste:0, waste:0 isolated, waste:1, where each bitset, where N0 = 8 * b0 and capacity = 8*(b1+1). The individual compressed bitsets, which indicates the index of the first byte in S, which indicates the minimal length in bytes (-1) of BS needed to contain all 1-bits in S. b1 is followed by b1+1 bytes, with a 1-bit. b1

Mastering Development System & Network

Enabling MySQL authentication for proftpd

Post author By Server Questions
Post date January 18, 2021
No Comments on Enabling MySQL authentication for proftpd

Mastering Development

C switch returns default inside if/else

Post author By Full Stack
Post date January 17, 2021
No Comments on C switch returns default inside if/else

I have the following problem: i have two switch cases . They work perfectly when separated, but the minute I put them into an if/else the 2. switch always returns the default(error).I am sorry for the difficult wording,now ive copied in the whole program so you can check it, ive tried what you said, but […]

Tags -, *, *), /, / default: printf("Error! operator is not correct"); } } return ; }, &b); switch(jel) { case '+': printf("%d + %d = %d", &b)) { switch(jel) { case '+': printf("%d", &donto); if(donto == 1) { printf("\nKerem irja be hanyadik szamokat szeretne es koze hogy milyen kalkulaciot szeretne vegezni(pl.: 5 + 8):\n", &jel, &jel); printf("add meg hanyadik szamokkal akarsz szamolni: "); scanf("%d %d", a, and no matter which I write in, B, but it didnt seem to help. So for an example, but the minute I put them into an if/else the 2. switch always returns the default(error).I am sorry for the difficult wording, donto; printf("\nKerem valassza ki milyen modon szeretne megadni az adatokat:\n 1.: egyben(peldaul 5. + 8.)\n 2.: kulon(peldaul + aztan 5. es, I have the following problem: i have two switch cases . They work perfectly when separated, it gives me the default output like ive wrote a wrong character. #include #include #include #include <math, ive tried what you said, j; for (i = 0; i < 10; ++i) { for (j = i + 1; j szamok[j]), my input is '2'. Then it asks for what character do I want to choose(+, now ive copied in the whole program so you can check it, scanf("%c", szamok[a-1]-szamok[b-1]); break; case '*': printf("%d", szamok[a-1]/szamok[b-1]); break; } } }else if (donto == 2) { printf("Adj meg egy jelet (+, szamok[a-1]+szamok[b-1]); break; case '-': printf("%d", szamok[a], szamok[a]-szamok[b]); break; case '*': printf("%d * %d = %d", szamok[a]/szamok[b]); break; // operator doesn't match any case constant +, szamok[a]+szamok[b]); break; case '-': printf("%d - %d = %d", szamok[b], szamok[i]); } return ; } void tomb_sorrend(int *szamok) { int i; int a, szamok[i]); } return; } void kalkulator(int *szamok) { char jel; int a, when it ask for the number

Mastering Development

Haskell. Sort by second element in the list of tuples

Post author By Full Stack
Post date January 17, 2021
No Comments on Haskell. Sort by second element in the list of tuples

I have a code histogram, which shows the number of all characters in String. histogram :: String -> [(Char, Int)] histogram = foldr help [] where help x [] = [(x,1)] help x ((y,z):yzs) | x == y = (y,z+1) : yzs | otherwise = (y,z) : help x yzs But the result is shown […]