改写val res = lines.map(lambda x:x.split(",")).filter(lambda x:x[0]=="Tom")
时间: 2023-06-08 15:05:42 浏览: 70
好的,我了解了。根据您的问题,这是一个对Spark以及Python语言的操作。对于给定的文本行,您想要使用逗号作为分隔符将其拆分,并返回包含名称为Tom的行的列表。改写如下:
```python
res = lines.map(lambda x: x.split(",")).filter(lambda x: x[0] == "Tom").collect()
```
上面的代码将执行以下操作:
1. 使用逗号作为分隔符将每个文本行拆分为字符串列表。
2. 过滤列表,选择第一个元素为“Tom”的行。
3. 将所选行作为列表收集并将其存储在变量“res”中。
希望这可以回答您的问题!
相关问题
用c语言写class ListNode: def __init__(self, x): self.val = x self.next = Nonedef mergeTwoLists(l1: ListNode, l2: ListNode) -> ListNode: if not l1: return l2 if not l2: return l1 if l1.val <= l2.val: head = l1 l1 = l1.next else: head = l2 l2 = l2.next cur = head while l1 and l2: if l1.val <= l2.val: cur.next = l1 l1 = l1.next else: cur.next = l2 l2 = l2.next cur = cur.next if l1: cur.next = l1 else: cur.next = l2 return head# 测试l1 = ListNode(1)l1.next = ListNode(3)l1.next.next = ListNode(5)l2 = ListNode(2)l2.next = ListNode(4)l2.next.next = ListNode(6)head = mergeTwoLists(l1, l2)while head: print(head.val, end=' ') head = head.next
以下是使用C语言实现的代码:
```c
#include <stdio.h>
#include <stdlib.h>
struct ListNode {
int val;
struct ListNode *next;
};
struct ListNode* mergeTwoLists(struct ListNode* l1, struct ListNode* l2){
if (!l1) return l2;
if (!l2) return l1;
struct ListNode *head, *cur;
if (l1->val <= l2->val) {
head = l1;
l1 = l1->next;
} else {
head = l2;
l2 = l2->next;
}
cur = head;
while (l1 && l2) {
if (l1->val <= l2->val) {
cur->next = l1;
l1 = l1->next;
} else {
cur->next = l2;
l2 = l2->next;
}
cur = cur->next;
}
if (l1) {
cur->next = l1;
} else {
cur->next = l2;
}
return head;
}
int main() {
struct ListNode *l1, *l2, *head;
l1 = (struct ListNode *)malloc(sizeof(struct ListNode));
l1->val = 1;
l1->next = (struct ListNode *)malloc(sizeof(struct ListNode));
l1->next->val = 3;
l1->next->next = (struct ListNode *)malloc(sizeof(struct ListNode));
l1->next->next->val = 5;
l1->next->next->next = NULL;
l2 = (struct ListNode *)malloc(sizeof(struct ListNode));
l2->val = 2;
l2->next = (struct ListNode *)malloc(sizeof(struct ListNode));
l2->next->val = 4;
l2->next->next = (struct ListNode *)malloc(sizeof(struct ListNode));
l2->next->next->val = 6;
l2->next->next->next = NULL;
head = mergeTwoLists(l1, l2);
while (head) {
printf("%d ", head->val);
head = head->next;
}
printf("\n");
return 0;
}
```
输出结果为:1 2 3 4 5 6
val mapstream = stream.map{x => { val arr = x.split(",") (arr(1), arr(2).toInt) }}是什么意思
这段代码的意思是,将一个流(stream)中的每个元素(x)按照逗号分隔符(",")进行切割(arr),然后将切割后的第二个元素(arr(1))作为键,第三个元素(arr(2).toInt)转化为整数后作为值,最终将这个键值对返回。这段代码利用了Scala语言的高阶函数(map)和元组(tuples)特性,可以方便地对数据进行转换和处理。