我想在一个拥有切片的结构上做一个函数。我的问题是:我想使用指针参数,因为我必须修改我的结构内容。
下面是我的代码:
type CampaignIndexMemory []CampaignIndex
type CampaignIndex struct {
Objects []CampaignIndexObject
}
type CampaignIndexObject struct {
//They don't really care about us
}
func (c *CampaignIndexMemory) setCampaignIndex(object Ca
有办法在go中创建不固定长度的片吗?例如,我想获取目录(content/)中对[] string片的所有填充。
content/ dir包含:
$-> tree content/
content/
├── 1.txt
├── 2.txt
└── tmp
我现在得到的是:
package main
import (
"fmt"
"io/ioutil"
)
func listFile() []string {
list := make([]string, 100)
// as you can see, I make a sl
package main
import "fmt"
func main() {
a := SomeType{myslice: []int{1, 2, 3}, decimal: 2.33}
for _, i := range a.myslice {
fmt.Println(i)
}
fmt.Println(a.decimal)
addOne(a)
for _, i := range a.myslice {
fmt.Println(i)
}
fmt.Println(a.dec
在这张幻灯片中,有一个片段:
package main
import "fmt"
func main() {
s := []int{2, 3, 5, 7, 11, 13}
printSlice(s)
// Slice the slice to give it zero length.
s = s[:0]
printSlice(s)
// Extend its length.
s = s[:4]
printSlice(s)
// Drop its first two values.
s =
我正在验证来自mariadb数据库的散列,但我不确定为什么必须获取数组的一部分,而不是只传递数组。 我在golang中对令牌进行散列,如下所示: // This type is a [32]uint8
tokenHash := sha256.Sum256(([]byte(token))) 然后,我尝试将令牌散列与此处保存在数据库中的散列进行匹配 // tokenHash[:] is of type []uint8
err := m.DB.QueryRowContext(ctx, query, tokenHash[:], time.Now()) 如果我没有获取切片,我得到的错误是:sql: c
我最近找到了一个解决问题的办法,我觉得这个问题很奇怪,我想更好地了解情况。这个问题涉及到在数组的指定索引处重写值.
import numpy as np
# create array to overwrite
mask = np.ones(10)
# first set of index-value pairs
idx_1 = [0, 3, 4]
val_1 = [100, 200, 300]
# second set of index-value pairs
idx_2 = [1, 5, 6]
val_2 = [250, 505, 650]
# third set of index-
我在Python中有这个子代码,我不能理解它是什么或它能做什么,特别是下面这句话:
X[:,:,:,i]
子码为:
train_dict = sio.loadmat(train_location)
X = np.asarray(train_dict['X'])
X_train = []
for i in range(X.shape[3]):
X_train.append(X[:,:,:,i])
X_train = np.asarray(X_train)
Y_train = train_dict['y']
for i in range(len(Y_tr
var a [4]int和b := make([]int, 4)有什么区别?b可以扩展,但不能扩展a,对吗?但是如果我知道我真的需要4个元素,那么数组比切片快吗?
var d []int和e := make([]int)之间有什么性能差异吗?对于第一个元素(即5个元素),f := make([]int, 5)会提供比没有长度的性能更好的性能吗?
这个c := make([]int, 5, 10)不会分配比我能访问的内存更多的内存吗?
我最近学习了Go语言,现在我对以下代码感到困惑:
package main
import "fmt"
func main() {
a := make([]int, 5)
printSlice("a", a)
b := make([]int, 0, 5)
printSlice("b", b)
c := b[:2]
printSlice("c", c)
d := c[2:5]
printSlice("d", d)
}
func printSlice(
我的代码:
package main
import (
"fmt"
)
func main() {
a := [10]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
b := a[1:4]
fmt.Println("a:", a)
fmt.Println("b:", b)
// Works fine even though c is indexing past the end of b.
c := b[4:7]
fmt.Println("c: