Wednesday 28 June 2017

Array

Notes for reading C++ Primer 4/e.

Dynamic Array

value-initialize

In dynamic array, it could only initial w/ default value, not like static array, could initial as different values.

int *pia = new int[10]();  // 10 ints w/ default value 0

const

Notes for reading C++ Primer 4/e.

const Reference

Reference to a constant object.

const int ival = 1024;
const int &refVal = ival;

const int &r = 42;
const int &r2 = r + 3;

const_iterator

for (vector<string>::const_iterator iter = text.begin();
iter != text.end(); ++iter) {
    *iter = " ";  // error: *iter is const
}

vector<int> nums(10);
const vector<int>::iterator cit = nums.begin();
*cit = 1;  // OK
++cit;  // error: cit is const

Pointers & const

Pointers to const

const double pi = 3.14;
double *ptr = &pi;  // error: nonconst pointer
const double *cptr = &pi;  // OK

double dval = 2.99;
cptr = &dval;  // OK

const Pointer

int errNumber = 0;
int *const curErr = &errNumber;
curErr = curErr;  // error: curErr is const

if (*curErr) {
    errorHandler();
    *curErr = 0;  // OK
}

const Pointer Point To A const Object

const double pi = 3.14159;
const double *const pi_ptr = &pi;

pi_ptr is a constant pointer, point to a const double object.

Pointers & Typedefs

typedef string *pstring;
const pstring cstr;

Q: What is cstr?
A: Constant point, point to string.

Tuesday 27 June 2017

Minor (Aeolian)

大調小調

自然/和聲/旋律小音階

Major Scale: 1 2 3 4 5 6 7
Nature Minor Scale: 1 2 b3 4 5 b6 b7
Harmonic Minor Scale: 1 2 b3 4 5 b6 7
Melodic Minor Scale: 1 2 b3 4 5 6 7 1 b7 b6 5 4 b3 2 1

Thursday 22 June 2017

Secondary Dominant

Learning notes of Secondary Dominant.

Secondary Dominant

什麼是大調小調？

Dominant

V -> I

讓 Dominant 更漂亮

ii -> V -> I or vii7(b5) -> V7 -> i

用 2-5-1

ii -> V -> I -> (Key - whole note) ii -> V -> I -> (Key - whole note) ii -> V -> I -> …

Advanced Reading

Secondary Dominant from GTCafe Studio
Q: 為什麼小調的 iv7 會變 IV7?
A: Harmonic Minor Scale

Wednesday 21 June 2017

How to Make Chord Progression

Learning how to make chord progression for a melody.

How to Make Chord Progression

如何幫一個旋律配上和弦？

使用和弦內音的方式來配置

用 C, G7, Dm 和 F

使用和弦內音的方式來配置並考慮 ii -> V -> I, I -> IV 等慣用進行

用大調 1-6 級

把 Tonic -> Sub-dominant -> Dominant -> Tonic 的感覺考慮進去
normally we use Tonic -> Sub-dominant or Tonic -> Dominant (but it’s more comfortable to use Tonic -> Sub-dominant -> Tonic) (1)
normally we use Sub-dominant -> Tonic or Sub-dominant -> Dominant (2)
normally we use Dominant -> Tonic (3)
先用 I, IV, V 配置，再用 (3), (2), (1) 修飾