transmute is semantically equivalent to a bitwise move of one typeinto another. It copies the bits from the source value into thedestination value, then forgets the original. Note that source and destinationare passed by-value, which means if Src or Dst contain padding, that paddingis not guaranteed to be preserved by transmute.
Both the argument and the result must be valid attheir given type. Violating this condition leads to undefined behavior. The compilerwill generate code assuming that you, the programmer, ensure that there will never beundefined behavior. It is therefore your responsibility to guarantee that every valuepassed to transmute is valid at both types Src and Dst. Failing to uphold this conditionmay lead to unexpected and unstable compilation results. This makes transmute incrediblyunsafe. transmute should be the absolute last resort.
Transmutation changes something over into something else. Thus, a writer may transmute his life into stories or novels, and an arranger might transmute a lively march tune into a quiet lullaby. In the \"Myth of Er\" at the end of Plato's Republic, for example, human souls are transmuted into the body and existence of their choice. Having learned from their last life what they do not want to be, many choose transmutation into something that seems better. A meek man chooses to be transmuted into a tyrant, a farmer into a dashing (but short-lived) warrior, and so on. But very few seem to have learned anything from their former life that would make their choice a real improvement.
This has been exacerbated today by hitting limitations in transmute in that it doesn't seem to support everything(). So I can't use it to add a new column and then include all the other columns after it. I'd like to be able to do:
@danr (update, sorry didn't fully read it) - I'm not trying to do any variable re-use here. I understand why that would need to be done in two steps. I'm questioning the need for transmute as a concept when select could be adapted to serve the same purpose.
Being a devil's advocate, there are plenty of other exceptions. transmute is one of them as is mutate which can be used to change existing columns as well as adding new ones. In theory adding new columns could be left to add_column with mutate only able to change existing ones.
transmute can also be used to select or re-order columns though, which is where I end up using select until there's something it can't do when I have to fall through to transmute. Sometimes I separate select and mutate, but sometimes it's clearer with a single transmute
@mungojam, am I right that the majority of the need for select helpers (specifically everything()) in transmute would go away for you if you could choose to insert the new columns from mutate on the \"left\" side of the data frame That seems like a smaller ask, in that inserting columns at the end/right doesn't seem inherent to the idea of creating a new column.
I think my mental difficulty with all this is that it is neither very strict nor very flexible. If it were very strict, then transmute would not exist and people would be forced to use a mixture of select, rename, mutate and add_column or add_columns and select wouldn't allow renaming while mutate wouldn't allow adding new columns. The way it is at present, I keep having to try things out to know if they will work or not because in theory they might work (like mutating in a select), but they might not.
In my head I don't really relate transmute strongly to mutate though the documentation strongly links them. I just see transmute as the only tool that gives me full(ish) flexibility in defining the columns I want in my tibble in whichever order I like and which can include transformed columns or constants if I want.
Agreed. What I was trying to get across (and still don't really have the right wording for) is that there's some potential ambiguity from a function standpoint. transmute(x = 2*y, everything()) could potentially mean that you create an x column followed by all remaining columns. However, it could also mean that you want to create an x column alongside a column called `everything()` that contains the result of that function that you've defined in your code. I doubt it's an insurmountable issue, but it shows an additional reason why separating the functionality of transmutate and select makes sense.
Regarding LLFPs, a transmutation study has recently been conducted on 6 important nuclides (79Se, 93Zr, 99Tc, 107Pd, 129I, and 135Cs) in terms of reducing environmental influence. As a result, it was shown that the fast reactor can be used to transmute each of these 6 nuclides with a support ratio exceeding 1 using the YD2 moderator28. A significant reduction in the effective half-life was obtained by analysis. In this case, the six nuclides were used as elements without isotope separation. In addition, a method that can transmute six nuclides at the same time with a support ratio of 1 or more in one fast reactor was clarified29. In this case, 135Cs and 93Zr, both with small neutron absorption cross sections, were placed in the radial blanket region, and 129I and 99Tc, both with large neutron absorption cross sections, were placed in the shield region and axial blanket away from the fuel region. Therefore, the transmutation rate of all nuclides was less than 0.5%/y. On the other hand, a study of a method designed to achieve a high transmutation rate (approximately 8%/y) for four nuclides (79Se, 99Tc, 107Pd, 129I) was conducted30. Based on these studies, a system that further improves the transmutation efficiency of the six nuclides was explored. A fast reactor LLFP transmutation system that achieves a support ratio of 1 or more for the entire system was constructed by combining three fast reactors, in addition to using one reactor31. From these studies, a substantial amount of information about the LLFP transmutation system was obtained.
Here, the support ratio (SR) was defined as the ratio of the amount of each nuclide transmuted by the fast breeder reactor to the amount of each nuclide (MAs and LLFPs) produced by the fast breeder reactor28,30,31.
From this study, the new concept of a fast breeder reactor system that can transmute MAs (237Np, 241Am, 243Am) and LLFPs (129I, 99Tc, 79Se) with a support ratio of 1 or more was constructed while breeding fissile materials in one fast breeder reactor. It was clarified that this fast breeder reactor achieved a breeding ratio of approximately 1.1 and MA and LLFP support ratios of 1 or more. The transmutation rate was 10.3%/y for 237Np, 14.1%/y for 241Am, 9.9%/y for 243Am, 1.6%/y for 129I, 0.75%/y for 99Tc, and 4%/y for 79Se.
The ability to breed fissile materials and transmute MAs and LLFPs in one fast breeder reactor shows the high potential of the fast breeder reactor and will promote research and development of the fast breeder reactor.
It allows the caster to transform one piece of unrefined Iron Ore to Silver Ore, and Silver Ore to Gold Ore. All you have to do is cast the spell and have either Iron or Silver Ore in your Misc inventory. It will automatically transmute the Iron to Silver and the Silver to Gold. If you have multiple Iron Ores, you will have to first Transmute a single Iron Ore to Silver and then to Gold before you can Transmute a second Iron Ore.
Transmuting one type to another type and vice versa in Rust is extremely dangerous ---so much so that the docs for std::mem::transmute are essentially a longlist of how to avoid doing so. However, transmuting is often times necessary especiallyin lower level contexts where copy of bytes is prohibitively expensive. For instance,in extremely performance-sensitive use cases, it may be necessary to transmute frombytes instead of explicitly copying bytes from a buffer into a struct.
Because of this fact, many external crateshave been developed to tackle this issue, but no single crate has managed to solidifyitself as a clear favorite in this space. Additionally, while it is possible to improveon unsafe transmute considerably in libraries, having such facilities in the standardlibrary opens up the possibility of bringing safe constructs to even more currentlyunsafe features.
The project group will start with a fairly limited scope, but if theinitial effort to design and stabilize APIs for safe transmute between types,there is at least one other area that can be expanded upon by this group: safe readingof union fields.
With a Storm Scale rating of 9, transmute is unlikely to see the light of day again anytime soon. Mark Rosewater suggests that whole mechanics built on tutoring are bad for the variability of the game.
Yes, you can copy transmute. Cards like Rings of Brighthearth can copy activated abilities like cycling and transmute, so the Rings let you tutor up two cards. And you can tutor up two different cards as long as they meet the mana value restriction since the Rings allow you to change the targets of the abilities.
It becomes further complicated when a spouse claims that property has been transmuted from one type of property to another. Transmutation means to change form, and in the context of California, Orange County divorce cases, transmutation means that property has changed form or character in one of the following ways:
Marital partners are free to transmute property between themselves during marriage. However, there are certain rules that apply to such transfers in order for them to be valid transmutations. Cal. Fam. Code 851 states simply that transmutations of property are subject to the laws prohibiting fraudulent transfers. This means that a person can transmute the character of item of marital or separate property in order to divest another person or creditor from their lawful right to that property. For example, if a spouse transfers a bank account to the name of a third party in order to hide the account from his or her spouse, such a transfer is illegal and will be set aside by the Oran